diff --git a/backend/version.py b/backend/version.py
index f4798f4..e4fa0a1 100644
--- a/backend/version.py
+++ b/backend/version.py
@@ -1,6 +1,6 @@
 # Shinkan Jinkendo Version Information
 
-APP_VERSION = "0.8.138"
+APP_VERSION = "0.8.139"
 BUILD_DATE = "2026-05-12"
 DB_SCHEMA_VERSION = "20260515063"
 
@@ -36,6 +36,13 @@ MODULE_VERSIONS = {
 }
 
 CHANGELOG = [
+    {
+        "version": "0.8.139",
+        "date": "2026-05-14",
+        "changes": [
+            "Frontend Trainingsplanung: GET phases → Editor mit planLoc pro Abschnitt; Speichern sendet PUT phases bei Breakout-Einheiten (sonst weiter sections); Modul-Dialog zeigt Phase/Stream in der Abschnittsauswahl.",
+        ],
+    },
     {
         "version": "0.8.138",
         "date": "2026-05-14",
diff --git a/frontend/src/components/planning/TrainingPlanningModuleApplyModal.jsx b/frontend/src/components/planning/TrainingPlanningModuleApplyModal.jsx
index 8d9ae91..61838b7 100644
--- a/frontend/src/components/planning/TrainingPlanningModuleApplyModal.jsx
+++ b/frontend/src/components/planning/TrainingPlanningModuleApplyModal.jsx
@@ -5,6 +5,18 @@ import { trainingVisibilityShortDE } from '../../utils/trainingPlanningPageHelpe
 /**
  * Dialog: Trainingsmodul in die Abschnitte einer Einheit einfügen (Bibliothekskopie).
  */
+
+function formatModuleApplySectionOptionLabel(section, flatIndex) {
+  const title = (section?.title || '').trim() || `Abschnitt ${flatIndex + 1}`
+  const pl = section?.planLoc
+  if (pl?.phaseKind === 'parallel') {
+    const st = (pl.streamTitle || '').trim()
+    const streamHint = st ? ` — ${st}` : ''
+    return `${title}${streamHint} (Phase ${pl.phaseOrderIndex ?? 0}, Stream ${pl.parallelStreamOrderIndex ?? 0})`
+  }
+  return title
+}
+
 export default function TrainingPlanningModuleApplyModal({
   open,
   busy,
@@ -101,7 +113,7 @@ export default function TrainingPlanningModuleApplyModal({
                   >
                     {(sections || []).map((s, i) => (
                       <option key={`sec-opt-u-${i}`} value={String(i)}>
-                        {(s.title || `Abschnitt ${i + 1}`).trim()}
+                        {formatModuleApplySectionOptionLabel(s, i)}
                       </option>
                     ))}
                   </select>
@@ -148,7 +160,7 @@ export default function TrainingPlanningModuleApplyModal({
               >
                 {(sections || []).map((s, i) => (
                   <option key={`sec-opt-${i}`} value={String(i)}>
-                    {(s.title || `Abschnitt ${i + 1}`).trim()}
+                    {formatModuleApplySectionOptionLabel(s, i)}
                   </option>
                 ))}
               </select>
diff --git a/frontend/src/components/planning/TrainingPlanningPageRoot.jsx b/frontend/src/components/planning/TrainingPlanningPageRoot.jsx
index 9f85400..1ce61ec 100644
--- a/frontend/src/components/planning/TrainingPlanningPageRoot.jsx
+++ b/frontend/src/components/planning/TrainingPlanningPageRoot.jsx
@@ -11,13 +11,12 @@ import TrainingPlanningFrameworkImportModal from './TrainingPlanningFrameworkImp
 import TrainingPlanningModuleApplyModal from './TrainingPlanningModuleApplyModal'
 import TrainingPlanningTrainerAssignModal from './TrainingPlanningTrainerAssignModal'
 import TrainingPlanningUnitFormModal from './TrainingPlanningUnitFormModal'
-/* Parallele Trainingsstreams (Breakout): Planungs-API bleibt flache sections/items bis Schema-Paket 1–2;
-   Payload-Aufbau → buildSectionsPayload (trainingUnitSectionsForm); Backend _replace_unit_sections. */
+/* Parallele Streams: Editor bleibt flache Abschnittsliste; `planLoc` pro Abschnitt steuert PUT `phases` vs. Legacy `sections`. */
 import {
   defaultSection,
   normalizeUnitToForm,
   enrichSectionsWithVariants,
-  buildSectionsPayload,
+  buildPlanPayloadForSave,
   hydrateExercisePlanningRow,
   insertTrainingModuleIntoPlanningSections,
 } from '../../utils/trainingUnitSectionsForm'
@@ -959,7 +958,7 @@ function TrainingPlanningPageRoot() {
       return
     }
     try {
-      const sectionsPayload = buildSectionsPayload(formData.sections)
+      const planPart = buildPlanPayloadForSave(formData.sections)
       const payload = {
         planned_date: formData.planned_date,
         planned_time_start: formData.planned_time_start || null,
@@ -972,7 +971,7 @@ function TrainingPlanningPageRoot() {
         status: formData.status || 'planned',
         notes: formData.notes || null,
         trainer_notes: formData.trainer_notes || null,
-        sections: sectionsPayload
+        ...planPart,
       }
       if (editingUnit) {
         payload.debrief_completed =
diff --git a/frontend/src/utils/trainingUnitSectionsForm.js b/frontend/src/utils/trainingUnitSectionsForm.js
index e6105d6..2f44e16 100644
--- a/frontend/src/utils/trainingUnitSectionsForm.js
+++ b/frontend/src/utils/trainingUnitSectionsForm.js
@@ -156,65 +156,132 @@ function parseOptionalSourceTrainingModuleIdForPayload(v) {
   return Number.isFinite(n) && n >= 1 ? n : null
 }
 
+function sortByOrderIndex(arr) {
+  return [...(arr || [])].sort((a, b) => (a.order_index ?? 0) - (b.order_index ?? 0))
+}
+
+/** Katalog-Abschnitt (GET) → Editor-Zeilen inkl. Kombi/Modul-Meta — wird von Legacy `sections` und von `phases` genutzt. */
+function formItemsFromApiItems(items) {
+  return (items || []).map((it) => {
+    if (it.item_type === 'note') {
+      const sm = parseOptionalSourceTrainingModuleIdForPayload(it.source_training_module_id)
+      const rowNote = {
+        item_type: 'note',
+        note_body: it.note_body || '',
+        source_training_module_id: '',
+        source_module_title: '',
+      }
+      if (sm != null) {
+        rowNote.source_training_module_id = sm
+        rowNote.source_module_title = (
+          it.source_module_title ||
+          it.source_training_module_title ||
+          ''
+        ).trim()
+      }
+      return rowNote
+    }
+    const smEx = parseOptionalSourceTrainingModuleIdForPayload(it.source_training_module_id)
+    const ek = String(it.exercise_kind || 'simple').toLowerCase().trim()
+    const isCombo = ek === 'combination'
+    return {
+      item_type: 'exercise',
+      exercise_id: it.exercise_id,
+      exercise_kind: isCombo ? 'combination' : 'simple',
+      exercise_variant_id: isCombo ? '' : it.exercise_variant_id ?? '',
+      exercise_title: it.exercise_title || '',
+      variants: [],
+      planned_duration_min:
+        it.planned_duration_min !== null && it.planned_duration_min !== undefined
+          ? String(it.planned_duration_min)
+          : '',
+      actual_duration_min:
+        it.actual_duration_min !== null && it.actual_duration_min !== undefined
+          ? String(it.actual_duration_min)
+          : '',
+      notes: it.notes ?? '',
+      modifications: it.modifications ?? '',
+      catalog_method_archetype: String(it.catalog_method_archetype ?? '').trim(),
+      catalog_method_profile: normalizeCatalogMethodProfile(it.catalog_method_profile),
+      planning_method_profile: normalizePlanningMethodProfile(it.planning_method_profile),
+      ...(smEx != null
+        ? {
+            source_training_module_id: smEx,
+            source_module_title: (
+              it.source_module_title ||
+              it.source_training_module_title ||
+              ''
+            ).trim(),
+          }
+        : {}),
+    }
+  })
+}
+
+/** GET `phases` → flache Editor-Abschnitte mit `planLoc` (für PUT `phases` Roundtrip). */
+function normalizePhasesToFormSections(fullUnit) {
+  const phases = sortByOrderIndex(fullUnit.phases || [])
+  const out = []
+  for (const ph of phases) {
+    const pOi = ph.order_index ?? 0
+    const pk = String(ph.phase_kind || 'whole_group').toLowerCase().trim()
+    const basePhaseLoc = {
+      phaseTitle: ph.title ?? null,
+      phaseGuidanceNotes: ph.guidance_notes ?? null,
+    }
+    if (pk === 'parallel') {
+      for (const st of sortByOrderIndex(ph.streams || [])) {
+        const sOi = st.order_index ?? 0
+        const streamLoc = {
+          phaseKind: 'parallel',
+          phaseOrderIndex: pOi,
+          parallelStreamOrderIndex: sOi,
+          ...basePhaseLoc,
+          streamTitle: st.title ?? null,
+          streamNotes: st.notes ?? null,
+          streamAssignedTrainerProfileIds: st.assigned_trainer_profile_ids ?? null,
+        }
+        for (const sec of sortByOrderIndex(st.sections || [])) {
+          out.push({
+            title: sec.title,
+            guidance_notes: sec.guidance_notes || '',
+            items: formItemsFromApiItems(sec.items),
+            planLoc: { ...streamLoc },
+          })
+        }
+      }
+    } else {
+      const loc = {
+        phaseKind: 'whole_group',
+        phaseOrderIndex: pOi,
+        parallelStreamOrderIndex: null,
+        ...basePhaseLoc,
+        streamTitle: null,
+        streamNotes: null,
+        streamAssignedTrainerProfileIds: null,
+      }
+      for (const sec of sortByOrderIndex(ph.sections || [])) {
+        out.push({
+          title: sec.title,
+          guidance_notes: sec.guidance_notes || '',
+          items: formItemsFromApiItems(sec.items),
+          planLoc: { ...loc },
+        })
+      }
+    }
+  }
+  return out.length ? out : [defaultSection()]
+}
+
 export function normalizeUnitToForm(fullUnit) {
+  if (Array.isArray(fullUnit?.phases) && fullUnit.phases.length > 0) {
+    return normalizePhasesToFormSections(fullUnit)
+  }
   if (fullUnit.sections && fullUnit.sections.length) {
     return fullUnit.sections.map((sec) => ({
       title: sec.title,
       guidance_notes: sec.guidance_notes || '',
-      items: (sec.items || []).map((it) => {
-        if (it.item_type === 'note') {
-          const sm = parseOptionalSourceTrainingModuleIdForPayload(it.source_training_module_id)
-          const rowNote = {
-            item_type: 'note',
-            note_body: it.note_body || '',
-            source_training_module_id: '',
-            source_module_title: '',
-          }
-          if (sm != null) {
-            rowNote.source_training_module_id = sm
-            rowNote.source_module_title = (
-              it.source_module_title ||
-              it.source_training_module_title ||
-              ''
-            ).trim()
-          }
-          return rowNote
-        }
-        const smEx = parseOptionalSourceTrainingModuleIdForPayload(it.source_training_module_id)
-        const ek = String(it.exercise_kind || 'simple').toLowerCase().trim()
-        const isCombo = ek === 'combination'
-        return {
-          item_type: 'exercise',
-          exercise_id: it.exercise_id,
-          exercise_kind: isCombo ? 'combination' : 'simple',
-          exercise_variant_id: isCombo ? '' : it.exercise_variant_id ?? '',
-          exercise_title: it.exercise_title || '',
-          variants: [],
-          planned_duration_min:
-            it.planned_duration_min !== null && it.planned_duration_min !== undefined
-              ? String(it.planned_duration_min)
-              : '',
-          actual_duration_min:
-            it.actual_duration_min !== null && it.actual_duration_min !== undefined
-              ? String(it.actual_duration_min)
-              : '',
-          notes: it.notes ?? '',
-          modifications: it.modifications ?? '',
-          catalog_method_archetype: String(it.catalog_method_archetype ?? '').trim(),
-          catalog_method_profile: normalizeCatalogMethodProfile(it.catalog_method_profile),
-          planning_method_profile: normalizePlanningMethodProfile(it.planning_method_profile),
-          ...(smEx != null
-            ? {
-                source_training_module_id: smEx,
-                source_module_title: (
-                  it.source_module_title ||
-                  it.source_training_module_title ||
-                  ''
-                ).trim(),
-              }
-            : {}),
-        }
-      }),
+      items: formItemsFromApiItems(sec.items),
     }))
   }
   if (fullUnit.exercises && fullUnit.exercises.length) {
@@ -398,10 +465,9 @@ export function parseMin(v) {
   return Number.isFinite(n) ? n : null
 }
 
-/** PUT /api/training-units/:id `sections` — flache order_index pro Einheit; Parallelität bricht am DB-UNIQUE (training_unit_id, order_index) bis Migration. */
-export function buildSectionsPayload(sections) {
-  return sections.map((sec, si) => ({
-    order_index: si,
+export function buildOneSectionPayload(sec, orderIndex) {
+  return {
+    order_index: orderIndex,
     title: (sec.title || '').trim() || 'Abschnitt',
     guidance_notes: sec.guidance_notes?.trim() ? sec.guidance_notes.trim() : null,
     items: (sec.items || [])
@@ -446,7 +512,110 @@ export function buildSectionsPayload(sections) {
         return rowEx
       })
       .filter(Boolean),
-  }))
+  }
+}
+
+/** PUT /api/training-units: Legacy `sections` (eine whole_group-Phase) wenn kein `planLoc` gesetzt ist. */
+export function buildSectionsPayload(sections) {
+  return sections.map((sec, si) => buildOneSectionPayload(sec, si))
+}
+
+function stripPlanLoc(sec) {
+  if (!sec || typeof sec !== 'object') return sec
+  const { planLoc: _pl, ...rest } = sec
+  return rest
+}
+
+function inheritPlanLocForPhasedSave(sections) {
+  let prev = {
+    phaseKind: 'whole_group',
+    phaseOrderIndex: 0,
+    parallelStreamOrderIndex: null,
+    phaseTitle: null,
+    phaseGuidanceNotes: null,
+    streamTitle: null,
+    streamNotes: null,
+    streamAssignedTrainerProfileIds: null,
+  }
+  return sections.map((s) => {
+    if (s?.planLoc && s.planLoc.phaseKind) {
+      prev = { ...s.planLoc }
+      return { ...s, planLoc: prev }
+    }
+    return { ...s, planLoc: { ...prev } }
+  })
+}
+
+function buildPhasesPayloadFromFlat(sections) {
+  const norm = inheritPlanLocForPhasedSave(sections)
+  const phases = []
+  let i = 0
+  while (i < norm.length) {
+    const loc0 = norm[i].planLoc
+    const pOi = loc0.phaseOrderIndex ?? 0
+    const pk = loc0.phaseKind === 'parallel' ? 'parallel' : 'whole_group'
+
+    const run = []
+    while (i < norm.length) {
+      const L = norm[i].planLoc
+      const pk2 = L.phaseKind === 'parallel' ? 'parallel' : 'whole_group'
+      if ((L.phaseOrderIndex ?? 0) !== pOi || pk2 !== pk) break
+      run.push(norm[i])
+      i += 1
+    }
+
+    const head = run[0].planLoc
+    if (pk === 'whole_group') {
+      phases.push({
+        phase_kind: 'whole_group',
+        order_index: pOi,
+        title: head.phaseTitle ?? null,
+        guidance_notes: head.phaseGuidanceNotes ?? null,
+        sections: run.map((s, idx) => buildOneSectionPayload(stripPlanLoc(s), idx)),
+      })
+    } else {
+      const byStream = new Map()
+      for (const s of run) {
+        const soi = s.planLoc.parallelStreamOrderIndex ?? 0
+        if (!byStream.has(soi)) byStream.set(soi, [])
+        byStream.get(soi).push(s)
+      }
+      const streamOrder = [...byStream.keys()].sort((a, b) => a - b)
+      const streams = streamOrder.map((soi) => {
+        const bucket = byStream.get(soi)
+        const h = bucket[0].planLoc
+        const st = {
+          order_index: soi,
+          title: h.streamTitle ?? null,
+          notes: h.streamNotes ?? null,
+          sections: bucket.map((s, idx) => buildOneSectionPayload(stripPlanLoc(s), idx)),
+        }
+        const asst = h.streamAssignedTrainerProfileIds
+        if (asst !== null && asst !== undefined) st.assigned_trainer_profile_ids = asst
+        return st
+      })
+      phases.push({
+        phase_kind: 'parallel',
+        order_index: pOi,
+        title: head.phaseTitle ?? null,
+        guidance_notes: head.phaseGuidanceNotes ?? null,
+        streams,
+      })
+    }
+  }
+  return { phases }
+}
+
+/**
+ * Speichern einer Einheit: flache `sections` oder verschachtelte `phases`, sobald `planLoc` gesetzt ist.
+ */
+export function buildPlanPayloadForSave(sections) {
+  const list = Array.isArray(sections) ? sections : []
+  const anyPhased = list.some((s) => s && s.planLoc && s.planLoc.phaseKind)
+  if (!anyPhased) {
+    return { sections: buildSectionsPayload(list) }
+  }
+  return buildPhasesPayloadFromFlat(list)
 }
 
 /** Fügt die Positionen eines Moduls in lokale Abschnitte ein (wie eine Übung, ohne Zwischenspeichern der Einheit). */