diff --git a/backend/migrations/021_roadmap_plan_snapshots.sql b/backend/migrations/021_roadmap_plan_snapshots.sql
new file mode 100644
index 0000000..91fff53
--- /dev/null
+++ b/backend/migrations/021_roadmap_plan_snapshots.sql
@@ -0,0 +1,17 @@
+-- AP1.14: Plan-Snapshots (Plan-Revision) — Soll-Zustand getrennt von Ist
+
+CREATE TABLE roadmap_plan_snapshots (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    tenant_id UUID NOT NULL REFERENCES tenants(id) ON DELETE CASCADE,
+    initiative_id UUID NOT NULL REFERENCES initiatives(id) ON DELETE CASCADE,
+    roadmap_id UUID NOT NULL REFERENCES roadmaps(id) ON DELETE CASCADE,
+    revision_number INT NOT NULL,
+    reason TEXT NOT NULL DEFAULT '',
+    plan_payload JSONB NOT NULL,
+    created_by_user_id UUID NULL REFERENCES users(id) ON DELETE SET NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    UNIQUE (tenant_id, initiative_id, revision_number)
+);
+
+CREATE INDEX idx_roadmap_plan_snapshots_initiative
+    ON roadmap_plan_snapshots(tenant_id, initiative_id, created_at DESC);
diff --git a/backend/routers/roadmap.py b/backend/routers/roadmap.py
index d9d249f..83e7020 100644
--- a/backend/routers/roadmap.py
+++ b/backend/routers/roadmap.py
@@ -10,6 +10,7 @@ from fastapi import APIRouter, Depends, HTTPException
 from pydantic import BaseModel, Field
 from services import roadmap as roadmap_service
 from services import roadmap_criteria as criteria_service
+from services import roadmap_plan_snapshot as snapshot_service
 from tenant_context import TenantContext
 
 router = APIRouter(tags=["roadmap"])
@@ -83,6 +84,10 @@ class ReopenRequest(BaseModel):
     reason: str = ""
 
 
+class PlanSnapshotCreateRequest(BaseModel):
+    reason: str = Field(default="", max_length=2000)
+
+
 initiative_router = APIRouter(prefix="/api/initiatives", tags=["roadmap"])
 items_router = APIRouter(prefix="/api/roadmap-items", tags=["roadmap"])
 deps_router = APIRouter(prefix="/api/roadmap-dependencies", tags=["roadmap"])
@@ -161,6 +166,49 @@ def get_initiative_roadmap_graph_state(
         raise HTTPException(status_code=400, detail=str(exc)) from exc
 
 
+@initiative_router.get("/{initiative_id}/roadmap/plan-ist-view")
+def get_initiative_plan_ist_view(
+    initiative_id: str,
+    ctx: TenantContext = Depends(require_capability("kairo.milestone.read")),
+):
+    try:
+        from steering.graph.plan_ist import load_plan_ist_view
+
+        return load_plan_ist_view(tenant_id=ctx.tenant_id, initiative_id=initiative_id)
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc
+
+
+@initiative_router.get("/{initiative_id}/roadmap/plan-snapshots")
+def list_initiative_plan_snapshots(
+    initiative_id: str,
+    ctx: TenantContext = Depends(require_capability("kairo.milestone.read")),
+):
+    try:
+        return snapshot_service.list_plan_snapshots(
+            tenant_id=ctx.tenant_id, initiative_id=initiative_id
+        )
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc
+
+
+@initiative_router.post("/{initiative_id}/roadmap/plan-snapshots", status_code=201)
+def create_initiative_plan_snapshot(
+    initiative_id: str,
+    body: PlanSnapshotCreateRequest,
+    ctx: TenantContext = Depends(require_capability("kairo.milestone.manage")),
+):
+    try:
+        return snapshot_service.create_plan_snapshot(
+            tenant_id=ctx.tenant_id,
+            initiative_id=initiative_id,
+            reason=body.reason,
+            user_id=ctx.user_id,
+        )
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc
+
+
 @initiative_router.post("/{initiative_id}/roadmap/items", status_code=201)
 def create_initiative_roadmap_item(
     initiative_id: str,
diff --git a/backend/services/roadmap_plan_snapshot.py b/backend/services/roadmap_plan_snapshot.py
new file mode 100644
index 0000000..cdae252
--- /dev/null
+++ b/backend/services/roadmap_plan_snapshot.py
@@ -0,0 +1,203 @@
+"""Plan snapshot capture & persistence (AP1.14)."""
+
+from __future__ import annotations
+
+import json
+from typing import Any, Optional
+
+from psycopg2.extras import RealDictCursor, Json
+
+from db import get_connection
+from services.audit import log_audit
+from services.initiatives import get_initiative
+from services import roadmap as roadmap_service
+from services import roadmap_criteria as criteria_service
+
+
+def _serialize_snapshot(row: dict[str, Any]) -> dict[str, Any]:
+    result = dict(row)
+    for key in ("id", "tenant_id", "initiative_id", "roadmap_id", "created_by_user_id"):
+        if result.get(key):
+            result[key] = str(result[key])
+    if result.get("created_at"):
+        result["created_at"] = result["created_at"].isoformat()
+    payload = result.get("plan_payload")
+    if isinstance(payload, str):
+        result["plan_payload"] = json.loads(payload)
+    return result
+
+
+def capture_plan_payload(
+    *, tenant_id: str, initiative_id: str
+) -> dict[str, Any]:
+    """Soll-Struktur: Topologie + Kriterien-Definitionen ohne Ist-Status."""
+    items = roadmap_service.list_roadmap_items_for_initiative(
+        tenant_id=tenant_id, initiative_id=initiative_id
+    )
+    dependencies = roadmap_service.list_dependencies_for_initiative(
+        tenant_id=tenant_id, initiative_id=initiative_id
+    )
+
+    plan_items = []
+    for item in items:
+        plan_items.append(
+            {
+                "id": item["id"],
+                "title": item["title"],
+                "item_type": item["item_type"],
+                "goal_description": item.get("goal_description") or "",
+                "sort_order": item.get("sort_order", 0),
+                "target_date": item.get("target_date"),
+                "sequencing_mode": item.get("sequencing_mode", "sequential"),
+            }
+        )
+
+    plan_deps = []
+    for dep in dependencies:
+        plan_deps.append(
+            {
+                "from_item_id": dep["from_item_id"],
+                "to_item_id": dep["to_item_id"],
+                "dependency_type": dep["dependency_type"],
+                "group_key": dep.get("group_key"),
+            }
+        )
+
+    plan_criteria = []
+    for item in items:
+        for crit in criteria_service.list_criteria_for_item(
+            tenant_id=tenant_id, item_id=item["id"]
+        ):
+            plan_criteria.append(
+                {
+                    "id": crit["id"],
+                    "roadmap_item_id": crit["roadmap_item_id"],
+                    "title": crit["title"],
+                    "description": crit.get("description") or "",
+                    "criterion_kind": crit["criterion_kind"],
+                    "sort_order": crit.get("sort_order", 0),
+                }
+            )
+
+    return {
+        "items": plan_items,
+        "dependencies": plan_deps,
+        "criteria": plan_criteria,
+    }
+
+
+def list_plan_snapshots(
+    *, tenant_id: str, initiative_id: str, limit: int = 20
+) -> list[dict[str, Any]]:
+    if not get_initiative(tenant_id=tenant_id, initiative_id=initiative_id):
+        raise ValueError("Initiative nicht gefunden")
+
+    conn = get_connection()
+    try:
+        with conn.cursor(cursor_factory=RealDictCursor) as cur:
+            cur.execute(
+                """
+                SELECT id, tenant_id, initiative_id, roadmap_id, revision_number,
+                       reason, plan_payload, created_by_user_id, created_at
+                FROM roadmap_plan_snapshots
+                WHERE tenant_id = %s AND initiative_id = %s
+                ORDER BY revision_number DESC
+                LIMIT %s
+                """,
+                (tenant_id, initiative_id, limit),
+            )
+            return [_serialize_snapshot(dict(r)) for r in cur.fetchall()]
+    finally:
+        conn.close()
+
+
+def get_plan_snapshot(
+    *, tenant_id: str, snapshot_id: str
+) -> Optional[dict[str, Any]]:
+    conn = get_connection()
+    try:
+        with conn.cursor(cursor_factory=RealDictCursor) as cur:
+            cur.execute(
+                """
+                SELECT id, tenant_id, initiative_id, roadmap_id, revision_number,
+                       reason, plan_payload, created_by_user_id, created_at
+                FROM roadmap_plan_snapshots
+                WHERE id = %s AND tenant_id = %s
+                """,
+                (snapshot_id, tenant_id),
+            )
+            row = cur.fetchone()
+            return _serialize_snapshot(dict(row)) if row else None
+    finally:
+        conn.close()
+
+
+def create_plan_snapshot(
+    *,
+    tenant_id: str,
+    initiative_id: str,
+    reason: str = "",
+    user_id: Optional[str] = None,
+) -> dict[str, Any]:
+    if not get_initiative(tenant_id=tenant_id, initiative_id=initiative_id):
+        raise ValueError("Initiative nicht gefunden")
+
+    roadmap = roadmap_service.get_roadmap_for_initiative(
+        tenant_id=tenant_id, initiative_id=initiative_id
+    )
+    if not roadmap:
+        raise ValueError("Roadmap nicht gefunden")
+
+    plan_payload = capture_plan_payload(tenant_id=tenant_id, initiative_id=initiative_id)
+    reason = reason.strip()
+
+    conn = get_connection()
+    try:
+        with conn.cursor(cursor_factory=RealDictCursor) as cur:
+            cur.execute(
+                """
+                SELECT COALESCE(MAX(revision_number), 0) + 1 AS next_rev
+                FROM roadmap_plan_snapshots
+                WHERE tenant_id = %s AND initiative_id = %s
+                """,
+                (tenant_id, initiative_id),
+            )
+            revision_number = int(cur.fetchone()["next_rev"])
+
+            cur.execute(
+                """
+                INSERT INTO roadmap_plan_snapshots (
+                    tenant_id, initiative_id, roadmap_id, revision_number,
+                    reason, plan_payload, created_by_user_id
+                )
+                VALUES (%s, %s, %s, %s, %s, %s, %s)
+                RETURNING id, tenant_id, initiative_id, roadmap_id, revision_number,
+                          reason, plan_payload, created_by_user_id, created_at
+                """,
+                (
+                    tenant_id,
+                    initiative_id,
+                    roadmap["id"],
+                    revision_number,
+                    reason,
+                    Json(plan_payload),
+                    user_id,
+                ),
+            )
+            row = _serialize_snapshot(dict(cur.fetchone()))
+        conn.commit()
+    finally:
+        conn.close()
+
+    log_audit(
+        "roadmap_plan_snapshot.created",
+        user_id=user_id,
+        tenant_id=tenant_id,
+        details={
+            "snapshot_id": row["id"],
+            "initiative_id": initiative_id,
+            "revision_number": revision_number,
+            "reason": reason or None,
+        },
+    )
+    return row
diff --git a/backend/steering/graph/plan_ist.py b/backend/steering/graph/plan_ist.py
new file mode 100644
index 0000000..dceb497
--- /dev/null
+++ b/backend/steering/graph/plan_ist.py
@@ -0,0 +1,283 @@
+"""Plan vs. Ist overlay and diff read models (AP1.14)."""
+
+from __future__ import annotations
+
+from typing import Any, Optional
+
+TERMINAL_IST_STATUSES = frozenset({"reached", "moved", "discarded"})
+IST_DEVIATION_CRITERION_STATUSES = frozenset({"waived", "deferred", "failed"})
+
+
+def _item_def_key(item: dict[str, Any]) -> str:
+    return str(item["id"])
+
+
+def _dep_key(dep: dict[str, Any]) -> str:
+    return (
+        f"{dep['from_item_id']}:{dep['to_item_id']}:"
+        f"{dep.get('dependency_type', 'requires')}"
+    )
+
+
+def _crit_def_key(crit: dict[str, Any]) -> str:
+    return str(crit["id"])
+
+
+def _structural_diff(
+    baseline: dict[str, Any], current: dict[str, Any]
+) -> list[dict[str, Any]]:
+    diffs: list[dict[str, Any]] = []
+
+    baseline_items = {_item_def_key(i): i for i in baseline.get("items", [])}
+    current_items = {_item_def_key(i): i for i in current.get("items", [])}
+
+    for item_id, item in current_items.items():
+        if item_id not in baseline_items:
+            diffs.append(
+                {
+                    "kind": "gate_added",
+                    "item_id": item_id,
+                    "title": item.get("title"),
+                    "message": "Gate im Plan neu seit letzter Revision",
+                }
+            )
+        else:
+            base = baseline_items[item_id]
+            if (
+                base.get("title") != item.get("title")
+                or base.get("goal_description") != item.get("goal_description")
+                or base.get("sort_order") != item.get("sort_order")
+            ):
+                diffs.append(
+                    {
+                        "kind": "gate_modified",
+                        "item_id": item_id,
+                        "title": item.get("title"),
+                        "message": "Gate-Definition geändert seit Revision",
+                    }
+                )
+
+    for item_id, item in baseline_items.items():
+        if item_id not in current_items:
+            diffs.append(
+                {
+                    "kind": "gate_removed",
+                    "item_id": item_id,
+                    "title": item.get("title"),
+                    "message": "Gate aus Plan entfernt seit Revision",
+                }
+            )
+
+    baseline_deps = {_dep_key(d): d for d in baseline.get("dependencies", [])}
+    current_deps = {_dep_key(d): d for d in current.get("dependencies", [])}
+    for key, dep in current_deps.items():
+        if key not in baseline_deps:
+            diffs.append(
+                {
+                    "kind": "edge_added",
+                    "item_id": dep["from_item_id"],
+                    "related_item_id": dep["to_item_id"],
+                    "message": "Neue Kante seit Revision",
+                }
+            )
+    for key, dep in baseline_deps.items():
+        if key not in current_deps:
+            diffs.append(
+                {
+                    "kind": "edge_removed",
+                    "item_id": dep["from_item_id"],
+                    "related_item_id": dep["to_item_id"],
+                    "message": "Kante entfernt seit Revision",
+                }
+            )
+
+    baseline_crit = {_crit_def_key(c): c for c in baseline.get("criteria", [])}
+    current_crit = {_crit_def_key(c): c for c in current.get("criteria", [])}
+    for crit_id, crit in current_crit.items():
+        if crit_id not in baseline_crit:
+            diffs.append(
+                {
+                    "kind": "criterion_added",
+                    "item_id": crit["roadmap_item_id"],
+                    "criterion_id": crit_id,
+                    "title": crit.get("title"),
+                    "message": "Kriterium neu seit Revision",
+                }
+            )
+        elif baseline_crit[crit_id].get("title") != crit.get("title"):
+            diffs.append(
+                {
+                    "kind": "criterion_modified",
+                    "item_id": crit["roadmap_item_id"],
+                    "criterion_id": crit_id,
+                    "title": crit.get("title"),
+                    "message": "Kriterium geändert seit Revision",
+                }
+            )
+    for crit_id, crit in baseline_crit.items():
+        if crit_id not in current_crit:
+            diffs.append(
+                {
+                    "kind": "criterion_removed",
+                    "item_id": crit["roadmap_item_id"],
+                    "criterion_id": crit_id,
+                    "title": crit.get("title"),
+                    "message": "Kriterium entfernt seit Revision",
+                }
+            )
+
+    return diffs
+
+
+def _ist_deviation_diff(
+    *,
+    items: list[dict[str, Any]],
+    criteria_by_item: dict[str, list[dict[str, Any]]],
+) -> list[dict[str, Any]]:
+    diffs: list[dict[str, Any]] = []
+
+    for item in items:
+        item_id = str(item["id"])
+        status = item.get("status", "planned")
+        if status in TERMINAL_IST_STATUSES:
+            diffs.append(
+                {
+                    "kind": "ist_gate_status",
+                    "item_id": item_id,
+                    "title": item.get("title"),
+                    "ist_status": status,
+                    "message": f"Ist-Status: {status}",
+                }
+            )
+        elif status == "at_risk":
+            diffs.append(
+                {
+                    "kind": "ist_gate_at_risk",
+                    "item_id": item_id,
+                    "title": item.get("title"),
+                    "ist_status": status,
+                    "message": "Gate als gefährdet markiert",
+                }
+            )
+
+        for crit in criteria_by_item.get(item_id, []):
+            crit_status = crit.get("status", "open")
+            if crit_status in IST_DEVIATION_CRITERION_STATUSES:
+                diffs.append(
+                    {
+                        "kind": f"ist_criterion_{crit_status}",
+                        "item_id": item_id,
+                        "criterion_id": crit["id"],
+                        "title": crit.get("title"),
+                        "ist_status": crit_status,
+                        "message": f"Kriterium {crit_status}: {crit.get('title')}",
+                    }
+                )
+
+    return diffs
+
+
+def build_plan_ist_view(
+    *,
+    tenant_id: str,
+    initiative_id: str,
+    snapshot: Optional[dict[str, Any]] = None,
+) -> dict[str, Any]:
+    from services import roadmap as roadmap_service
+    from services import roadmap_criteria as criteria_service
+    from services.roadmap_plan_snapshot import capture_plan_payload
+    from steering.graph.roadmap_engine import load_initiative_graph_state
+
+    live_items = roadmap_service.list_roadmap_items_for_initiative(
+        tenant_id=tenant_id, initiative_id=initiative_id
+    )
+    current_plan = capture_plan_payload(tenant_id=tenant_id, initiative_id=initiative_id)
+    graph_state = load_initiative_graph_state(
+        tenant_id=tenant_id, initiative_id=initiative_id
+    )
+
+    baseline_plan = snapshot["plan_payload"] if snapshot else current_plan
+    plan_source = "snapshot" if snapshot else "live"
+
+    criteria_by_item: dict[str, list[dict[str, Any]]] = {}
+    ist_items = []
+    for item in live_items:
+        item_id = str(item["id"])
+        criteria = criteria_service.list_criteria_for_item(
+            tenant_id=tenant_id, item_id=item_id
+        )
+        criteria_by_item[item_id] = criteria
+        graph_item = graph_state.get("items", {}).get(item_id, {})
+        ist_items.append(
+            {
+                "id": item_id,
+                "title": item["title"],
+                "status": item["status"],
+                "fulfillment_ratio": graph_item.get("fulfillment_ratio"),
+                "blocked": graph_item.get("blocked"),
+                "ready": graph_item.get("ready"),
+                "criteria": [
+                    {
+                        "id": c["id"],
+                        "title": c["title"],
+                        "status": c["status"],
+                        "criterion_kind": c["criterion_kind"],
+                    }
+                    for c in criteria
+                ],
+            }
+        )
+
+    diff: list[dict[str, Any]] = []
+    if snapshot:
+        diff.extend(_structural_diff(baseline_plan, current_plan))
+    diff.extend(
+        _ist_deviation_diff(items=live_items, criteria_by_item=criteria_by_item)
+    )
+
+    latest_meta = None
+    if snapshot:
+        latest_meta = {
+            "id": snapshot["id"],
+            "revision_number": snapshot["revision_number"],
+            "reason": snapshot.get("reason") or "",
+            "created_at": snapshot.get("created_at"),
+        }
+
+    return {
+        "initiative_id": initiative_id,
+        "plan_source": plan_source,
+        "latest_snapshot": latest_meta,
+        "plan": baseline_plan,
+        "current_plan": current_plan if snapshot else None,
+        "ist": {
+            "items": ist_items,
+            "graph_state": {
+                "method_key": graph_state.get("method_key"),
+                "graph_profile": graph_state.get("graph_profile"),
+                "initiative_fulfillment_ratio": graph_state.get(
+                    "initiative_fulfillment_ratio"
+                ),
+            },
+        },
+        "diff": diff,
+        "diff_count": len(diff),
+    }
+
+
+def load_plan_ist_view(*, tenant_id: str, initiative_id: str) -> dict[str, Any]:
+    from services.initiatives import get_initiative
+    from services.roadmap_plan_snapshot import list_plan_snapshots
+
+    if not get_initiative(tenant_id=tenant_id, initiative_id=initiative_id):
+        raise ValueError("Initiative nicht gefunden")
+
+    snapshots = list_plan_snapshots(
+        tenant_id=tenant_id, initiative_id=initiative_id, limit=1
+    )
+    snapshot = snapshots[0] if snapshots else None
+    return build_plan_ist_view(
+        tenant_id=tenant_id,
+        initiative_id=initiative_id,
+        snapshot=snapshot,
+    )
diff --git a/backend/tests/test_ap14_plan_ist.py b/backend/tests/test_ap14_plan_ist.py
new file mode 100644
index 0000000..734145d
--- /dev/null
+++ b/backend/tests/test_ap14_plan_ist.py
@@ -0,0 +1,34 @@
+"""Unit tests for plan/ist overlay (AP1.14)."""
+
+from steering.graph.plan_ist import _ist_deviation_diff, _structural_diff
+
+
+def test_structural_diff_detects_added_gate():
+    baseline = {"items": [{"id": "a", "title": "A", "goal_description": "", "sort_order": 0}], "dependencies": [], "criteria": []}
+    current = {
+        "items": [
+            {"id": "a", "title": "A", "goal_description": "", "sort_order": 0},
+            {"id": "b", "title": "B", "goal_description": "", "sort_order": 1},
+        ],
+        "dependencies": [],
+        "criteria": [],
+    }
+    diffs = _structural_diff(baseline, current)
+    assert any(d["kind"] == "gate_added" and d["item_id"] == "b" for d in diffs)
+
+
+def test_ist_deviation_detects_reached_gate():
+    items = [{"id": "g1", "title": "Gate", "status": "reached"}]
+    diffs = _ist_deviation_diff(items=items, criteria_by_item={"g1": []})
+    assert any(d["kind"] == "ist_gate_status" for d in diffs)
+
+
+def test_ist_deviation_detects_waived_criterion():
+    items = [{"id": "g1", "title": "Gate", "status": "active"}]
+    criteria = {
+        "g1": [
+            {"id": "c1", "title": "Kriterium", "status": "waived", "criterion_kind": "manual"}
+        ]
+    }
+    diffs = _ist_deviation_diff(items=items, criteria_by_item=criteria)
+    assert any(d["kind"] == "ist_criterion_waived" for d in diffs)
diff --git a/backend/tests/test_ap14_roadmap.py b/backend/tests/test_ap14_roadmap.py
index 59d0cd8..b43f046 100644
--- a/backend/tests/test_ap14_roadmap.py
+++ b/backend/tests/test_ap14_roadmap.py
@@ -269,3 +269,51 @@ def test_graph_blocked_attention_for_gate_enforcing_method(client):
         i["kind"] == "gate_graph_blocked" and i["milestone_id"] == gate_a["id"]
         for i in attention.json()
     )
+
+
+def test_plan_ist_view_and_snapshot(client):
+    user = provision_user_in_tenant(tenant_role="member")
+    token = _login(client, user)
+    initiative_id = _create_initiative(client, token).json()["id"]
+    gate = _create_roadmap_item(client, token, initiative_id, title="Gate Plan").json()
+
+    view = client.get(
+        f"/api/initiatives/{initiative_id}/roadmap/plan-ist-view",
+        headers=_auth(token),
+    )
+    assert view.status_code == 200
+    body = view.json()
+    assert body["plan_source"] == "live"
+    assert len(body["plan"]["items"]) >= 1
+    assert body["latest_snapshot"] is None
+
+    snap = client.post(
+        f"/api/initiatives/{initiative_id}/roadmap/plan-snapshots",
+        json={"reason": "Baseline vor Umsetzung"},
+        headers=_auth(token),
+    )
+    assert snap.status_code == 201
+    assert snap.json()["revision_number"] == 1
+
+    view2 = client.get(
+        f"/api/initiatives/{initiative_id}/roadmap/plan-ist-view",
+        headers=_auth(token),
+    )
+    assert view2.status_code == 200
+    body2 = view2.json()
+    assert body2["plan_source"] == "snapshot"
+    assert body2["latest_snapshot"]["revision_number"] == 1
+
+    patched = client.patch(
+        f"/api/roadmap-items/{gate['id']}",
+        json={"title": "Gate umbenannt"},
+        headers=_auth(token),
+    )
+    assert patched.status_code == 200
+
+    view3 = client.get(
+        f"/api/initiatives/{initiative_id}/roadmap/plan-ist-view",
+        headers=_auth(token),
+    )
+    diff_kinds = {d["kind"] for d in view3.json()["diff"]}
+    assert "gate_modified" in diff_kinds
diff --git a/frontend/src/App.jsx b/frontend/src/App.jsx
index 2fc76f9..0c9eec1 100644
--- a/frontend/src/App.jsx
+++ b/frontend/src/App.jsx
@@ -79,6 +79,7 @@ function AppRoutes() {
           <Route path="/control" element={<ControlLayout />}>
             <Route index element={<ControlIndexRedirect />} />
             <Route path="status" element={<MODE_ROUTE_COMPONENTS.controlStatus />} />
+            <Route path="plan-ist" element={<MODE_ROUTE_COMPONENTS.controlPlanIst />} />
             <Route path="journey" element={<MODE_ROUTE_COMPONENTS.controlJourney />} />
           </Route>
 
diff --git a/frontend/src/api/roadmap.js b/frontend/src/api/roadmap.js
index 31d7d09..5c39ad9 100644
--- a/frontend/src/api/roadmap.js
+++ b/frontend/src/api/roadmap.js
@@ -16,6 +16,21 @@ export function listInitiativeRoadmapGraphState(initiativeId) {
   return apiFetch(`/api/initiatives/${initiativeId}/roadmap/graph-state`)
 }
 
+export function getInitiativePlanIstView(initiativeId) {
+  return apiFetch(`/api/initiatives/${initiativeId}/roadmap/plan-ist-view`)
+}
+
+export function listInitiativePlanSnapshots(initiativeId) {
+  return apiFetch(`/api/initiatives/${initiativeId}/roadmap/plan-snapshots`)
+}
+
+export function createInitiativePlanSnapshot(initiativeId, body) {
+  return apiFetch(`/api/initiatives/${initiativeId}/roadmap/plan-snapshots`, {
+    method: 'POST',
+    body: JSON.stringify(body),
+  })
+}
+
 export function createInitiativeRoadmapItem(initiativeId, body) {
   return apiFetch(`/api/initiatives/${initiativeId}/roadmap/items`, {
     method: 'POST',
diff --git a/frontend/src/components/PlanIstPanel.jsx b/frontend/src/components/PlanIstPanel.jsx
new file mode 100644
index 0000000..6cfc238
--- /dev/null
+++ b/frontend/src/components/PlanIstPanel.jsx
@@ -0,0 +1,272 @@
+import { useCallback, useEffect, useState } from 'react'
+import { Link } from 'react-router-dom'
+import {
+  getInitiativePlanIstView,
+  createInitiativePlanSnapshot,
+} from '../api/roadmap.js'
+import { gatePath } from '../utils/routes.js'
+import {
+  CRITERION_STATUS_LABELS,
+  MILESTONE_STATUS_LABELS,
+  ROADMAP_ITEM_TYPE_LABELS,
+} from '../constants/status.js'
+import { LoadingState } from './LoadingState.jsx'
+import { ErrorState } from './ErrorState.jsx'
+import { Modal } from './Modal.jsx'
+import { EmptyState } from './EmptyState.jsx'
+
+const DIFF_KIND_LABELS = {
+  gate_added: 'Gate neu',
+  gate_removed: 'Gate entfernt',
+  gate_modified: 'Gate geändert',
+  edge_added: 'Kante neu',
+  edge_removed: 'Kante entfernt',
+  criterion_added: 'Kriterium neu',
+  criterion_removed: 'Kriterium entfernt',
+  criterion_modified: 'Kriterium geändert',
+  ist_gate_status: 'Ist-Status Gate',
+  ist_gate_at_risk: 'Gate gefährdet',
+  ist_criterion_waived: 'Kriterium ausgelassen',
+  ist_criterion_deferred: 'Kriterium verschoben',
+  ist_criterion_failed: 'Kriterium fehlgeschlagen',
+}
+
+function formatPct(ratio) {
+  if (ratio == null) return null
+  return `${Math.round(ratio * 100)}%`
+}
+
+export function PlanIstPanel({ initiativeId, canManage = false }) {
+  const [view, setView] = useState(null)
+  const [loading, setLoading] = useState(true)
+  const [error, setError] = useState(null)
+  const [tab, setTab] = useState('plan')
+  const [busy, setBusy] = useState(false)
+  const [showRevision, setShowRevision] = useState(false)
+  const [revisionReason, setRevisionReason] = useState('')
+
+  const load = useCallback(async () => {
+    if (!initiativeId) return
+    setLoading(true)
+    setError(null)
+    try {
+      setView(await getInitiativePlanIstView(initiativeId))
+    } catch (err) {
+      setError(err.message)
+    } finally {
+      setLoading(false)
+    }
+  }, [initiativeId])
+
+  useEffect(() => {
+    load()
+  }, [load])
+
+  async function handleCreateRevision(e) {
+    e.preventDefault()
+    setBusy(true)
+    setError(null)
+    try {
+      await createInitiativePlanSnapshot(initiativeId, {
+        reason: revisionReason.trim(),
+      })
+      setRevisionReason('')
+      setShowRevision(false)
+      await load()
+    } catch (err) {
+      setError(err.message)
+    } finally {
+      setBusy(false)
+    }
+  }
+
+  if (loading) return <LoadingState message="Plan/Ist wird geladen…" />
+  if (error && !view) return <ErrorState message={error} onRetry={load} />
+  if (!view) return null
+
+  const planItems = view.plan?.items || []
+  const istItems = view.ist?.items || []
+  const diffs = view.diff || []
+
+  return (
+    <section className="card plan-ist-panel">
+      <div className="section-header">
+        <div>
+          <h2>Plan vs. Ist</h2>
+          <p className="section-lead muted">
+            Soll-Graph und Ist-Overlay parallel — Abweichungen sichtbar, Plan-Revision mit Audit.
+          </p>
+          {view.latest_snapshot ? (
+            <p className="muted plan-ist-panel__snapshot-meta">
+              Baseline: Revision {view.latest_snapshot.revision_number}
+              {view.latest_snapshot.reason ? ` — ${view.latest_snapshot.reason}` : ''}
+            </p>
+          ) : (
+            <p className="muted plan-ist-panel__snapshot-meta">
+              Noch keine Plan-Revision — aktueller Plan = live. Revision festhalten vor größeren
+              Änderungen.
+            </p>
+          )}
+        </div>
+        {canManage && (
+          <button
+            type="button"
+            className="btn btn-primary btn-sm"
+            onClick={() => setShowRevision(true)}
+            disabled={busy}
+          >
+            Plan-Revision
+          </button>
+        )}
+      </div>
+
+      {error && <p className="error">{error}</p>}
+
+      <div className="plan-ist-panel__tabs" role="tablist" aria-label="Plan Ist Diff">
+        {['plan', 'ist', 'diff'].map((key) => (
+          <button
+            key={key}
+            type="button"
+            role="tab"
+            aria-selected={tab === key}
+            className={
+              'plan-ist-panel__tab' + (tab === key ? ' plan-ist-panel__tab--active' : '')
+            }
+            onClick={() => setTab(key)}
+          >
+            {key === 'plan' ? 'Plan (Soll)' : key === 'ist' ? 'Ist' : `Diff (${diffs.length})`}
+          </button>
+        ))}
+      </div>
+
+      {tab === 'plan' && (
+        <div className="plan-ist-panel__pane">
+          {planItems.length === 0 && (
+            <EmptyState message="Kein Plan — Zielzustände unter Planen anlegen." />
+          )}
+          <ul className="item-list">
+            {planItems.map((item) => (
+              <li key={item.id} className="list-item card-list-item">
+                <div className="list-item-main">
+                  <strong>
+                    <Link to={gatePath(item.id)}>{item.title}</Link>
+                  </strong>
+                  <p className="muted list-item-sub">
+                    {ROADMAP_ITEM_TYPE_LABELS[item.item_type] || item.item_type}
+                    {item.target_date ? ` · Ziel ${item.target_date}` : ''}
+                  </p>
+                  {item.goal_description && (
+                    <p className="list-item-desc">{item.goal_description}</p>
+                  )}
+                </div>
+              </li>
+            ))}
+          </ul>
+          {view.plan_source === 'snapshot' && view.current_plan && (
+            <p className="muted plan-ist-panel__hint">
+              Live-Plan weicht von Revision ab — siehe Diff.
+            </p>
+          )}
+        </div>
+      )}
+
+      {tab === 'ist' && (
+        <div className="plan-ist-panel__pane">
+          {view.ist?.graph_state?.initiative_fulfillment_ratio != null && (
+            <p className="plan-ist-panel__fulfillment muted">
+              Erfüllungsgrad:{' '}
+              {formatPct(view.ist.graph_state.initiative_fulfillment_ratio)}
+            </p>
+          )}
+          <ul className="item-list">
+            {istItems.map((item) => (
+              <li key={item.id} className="list-item card-list-item">
+                <div className="list-item-main">
+                  <strong>
+                    <Link to={gatePath(item.id)}>{item.title}</Link>
+                  </strong>
+                  <p className="muted list-item-sub">
+                    {MILESTONE_STATUS_LABELS[item.status] || item.status}
+                    {item.fulfillment_ratio != null
+                      ? ` · ${formatPct(item.fulfillment_ratio)} Kriterien`
+                      : ''}
+                  </p>
+                  {item.criteria?.length > 0 && (
+                    <ul className="plan-ist-panel__criteria muted">
+                      {item.criteria.map((crit) => (
+                        <li key={crit.id}>
+                          {crit.title}:{' '}
+                          {CRITERION_STATUS_LABELS[crit.status] || crit.status}
+                        </li>
+                      ))}
+                    </ul>
+                  )}
+                </div>
+              </li>
+            ))}
+          </ul>
+        </div>
+      )}
+
+      {tab === 'diff' && (
+        <div className="plan-ist-panel__pane">
+          {diffs.length === 0 && (
+            <EmptyState message="Keine Abweichungen — Plan und Ist sind konsistent." />
+          )}
+          <ul className="item-list">
+            {diffs.map((entry, index) => (
+              <li key={`${entry.kind}-${entry.item_id}-${index}`} className="list-item card-list-item">
+                <div className="list-item-main">
+                  <span className="status-pill plan-ist-panel__diff-kind">
+                    {DIFF_KIND_LABELS[entry.kind] || entry.kind}
+                  </span>
+                  <strong>{entry.title || entry.message}</strong>
+                  <p className="muted list-item-desc">{entry.message}</p>
+                </div>
+                {entry.item_id && (
+                  <div className="list-item-meta">
+                    <Link to={gatePath(entry.item_id)} className="btn btn-secondary btn-sm">
+                      Gate
+                    </Link>
+                  </div>
+                )}
+              </li>
+            ))}
+          </ul>
+        </div>
+      )}
+
+      <Modal open={showRevision} title="Plan-Revision festhalten" onClose={() => setShowRevision(false)}>
+        <form className="form workspace-form" onSubmit={handleCreateRevision}>
+          <p className="muted form-hint">
+            Speichert Topologie, Kanten und Kriterien-Definitionen als Soll-Baseline — Ist-Status
+            bleibt getrennt.
+          </p>
+          <label>
+            Begründung (optional)
+            <textarea
+              value={revisionReason}
+              onChange={(e) => setRevisionReason(e.target.value)}
+              rows={3}
+              maxLength={2000}
+              placeholder="z. B. Scope-Freeze vor Release 1"
+            />
+          </label>
+          <div className="form-actions">
+            <button type="submit" className="btn btn-primary" disabled={busy}>
+              {busy ? 'Speichern …' : 'Revision anlegen'}
+            </button>
+            <button
+              type="button"
+              className="btn btn-secondary"
+              onClick={() => setShowRevision(false)}
+              disabled={busy}
+            >
+              Abbrechen
+            </button>
+          </div>
+        </form>
+      </Modal>
+    </section>
+  )
+}
diff --git a/frontend/src/config/controlNav.js b/frontend/src/config/controlNav.js
index 26c27a3..874924c 100644
--- a/frontend/src/config/controlNav.js
+++ b/frontend/src/config/controlNav.js
@@ -8,6 +8,7 @@
 /** @type {ModeNavItem[]} */
 export const CONTROL_NAV_ITEMS = [
   { key: 'status', to: '/control/status', label: 'Steuerung' },
+  { key: 'plan-ist', to: '/control/plan-ist', label: 'Plan / Ist' },
   { key: 'journey', to: '/control/journey', label: 'Nachvollziehbarkeit' },
 ]
 
diff --git a/frontend/src/config/modeNav.test.js b/frontend/src/config/modeNav.test.js
index da4b78a..217caa7 100644
--- a/frontend/src/config/modeNav.test.js
+++ b/frontend/src/config/modeNav.test.js
@@ -5,6 +5,7 @@ import { resolveWorkNavActiveKey } from '../config/workNav.js'
 describe('controlNav', () => {
   it('resolves active control sub-route', () => {
     expect(resolveControlNavActiveKey('/control/status')).toBe('status')
+    expect(resolveControlNavActiveKey('/control/plan-ist')).toBe('plan-ist')
     expect(resolveControlNavActiveKey('/control/journey')).toBe('journey')
     expect(resolveControlNavActiveKey('/control')).toBe(null)
   })
diff --git a/frontend/src/pages/modes/ControlPlanIstPage.jsx b/frontend/src/pages/modes/ControlPlanIstPage.jsx
new file mode 100644
index 0000000..c70911c
--- /dev/null
+++ b/frontend/src/pages/modes/ControlPlanIstPage.jsx
@@ -0,0 +1,24 @@
+import { RequireInitiativeScope } from '../../components/RequireInitiativeScope.jsx'
+import { ScopedInitiativeProvider } from '../../layout/ScopedInitiativeProvider.jsx'
+import { PlanIstPanel } from '../../components/PlanIstPanel.jsx'
+import { useInitiativeOperations } from '../../context/InitiativeOperationsContext.jsx'
+
+function PlanIstContent() {
+  const { initiativeId, capabilities } = useInitiativeOperations()
+  return (
+    <PlanIstPanel
+      initiativeId={initiativeId}
+      canManage={capabilities.has('kairo.milestone.manage')}
+    />
+  )
+}
+
+export function ControlPlanIstPage() {
+  return (
+    <RequireInitiativeScope lead="Plan/Ist-Vergleich braucht ein Vorhaben im Scope.">
+      <ScopedInitiativeProvider>
+        <PlanIstContent />
+      </ScopedInitiativeProvider>
+    </RequireInitiativeScope>
+  )
+}
diff --git a/frontend/src/registry/viewRegistry.js b/frontend/src/registry/viewRegistry.js
index 7af574f..c11420c 100644
--- a/frontend/src/registry/viewRegistry.js
+++ b/frontend/src/registry/viewRegistry.js
@@ -11,6 +11,7 @@ import { PlanProfilePage } from '../pages/modes/PlanProfilePage.jsx'
 import { PlanPortfolioPage } from '../pages/modes/PlanPortfolioPage.jsx'
 import { ControlLayout, ControlIndexRedirect } from '../pages/modes/ControlLayout.jsx'
 import { ControlStatusPage } from '../pages/modes/ControlStatusPage.jsx'
+import { ControlPlanIstPage } from '../pages/modes/ControlPlanIstPage.jsx'
 import { ControlJourneyPage } from '../pages/modes/ControlJourneyPage.jsx'
 import { TeamPage } from '../pages/modes/TeamPage.jsx'
 import { InitiativesPage } from '../pages/InitiativesPage.jsx'
@@ -135,6 +136,7 @@ export const MODE_ROUTE_COMPONENTS = {
   planInbox: PlanInboxPage,
   planWork: PlanWorkPage,
   controlStatus: ControlStatusPage,
+  controlPlanIst: ControlPlanIstPage,
   controlJourney: ControlJourneyPage,
 }
 
diff --git a/frontend/src/styles/components.css b/frontend/src/styles/components.css
index 4152510..761b856 100644
--- a/frontend/src/styles/components.css
+++ b/frontend/src/styles/components.css
@@ -1813,6 +1813,44 @@
   font-size: 0.875rem;
 }
 
+.plan-ist-panel__tabs {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 0.5rem;
+  margin-bottom: 1rem;
+}
+
+.plan-ist-panel__tab {
+  padding: 0.35rem 0.75rem;
+  border: 1px solid var(--jk-border-strong, #c5ced8);
+  border-radius: 999px;
+  background: transparent;
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+.plan-ist-panel__tab--active {
+  background: var(--jk-surface-muted, #eef2f6);
+  font-weight: 600;
+}
+
+.plan-ist-panel__snapshot-meta,
+.plan-ist-panel__hint,
+.plan-ist-panel__fulfillment {
+  font-size: 0.875rem;
+  margin-top: 0.35rem;
+}
+
+.plan-ist-panel__criteria {
+  margin: 0.35rem 0 0;
+  padding-left: 1.1rem;
+  font-size: 0.8125rem;
+}
+
+.plan-ist-panel__diff-kind {
+  margin-right: 0.5rem;
+}
+
 .gate-map-view__node-title {
   fill: var(--jk-text, #1a1a1a);
   font-size: 14px;