diff --git a/.github/workflows/reusable-code.yml b/.github/workflows/reusable-code.yml
index 5ed01ebaf..0cdbbbf23 100644
--- a/.github/workflows/reusable-code.yml
+++ b/.github/workflows/reusable-code.yml
@@ -1,5 +1,8 @@
-# Reusable code agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable code agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled).
 name: Code Agent
 
 on:
@@ -39,6 +42,10 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: fullsend-code-agent-${{ inputs.source_repo }}-${{ fromJSON(inputs.event_payload).issue.number }}
+  cancel-in-progress: true
+
 jobs:
   code:
     name: Code
diff --git a/.github/workflows/reusable-dispatch.yml b/.github/workflows/reusable-dispatch.yml
index 95bf3cb4d..a0cf0d775 100644
--- a/.github/workflows/reusable-dispatch.yml
+++ b/.github/workflows/reusable-dispatch.yml
@@ -3,6 +3,11 @@
 # workflow_call jobs. This is the per-repo equivalent of the per-org
 # dispatch.yml + thin caller pair.
 #
+# Concurrency: each stage job declares a per-role cancel-in-progress dispatch group.
+# Reusable stage workflows use distinct agent-scoped groups (fullsend-{stage}-agent-…)
+# so workflow_call parents are not cancelled. Roles operate independently — review
+# dispatches do not cancel triage, code, fix, etc.
+#
 # Flow: shim (per-repo) → reusable-dispatch.yml → reusable-{stage}.yml
 # Nesting: 3 levels of workflow_call (within GitHub's 4-level limit)
 #
@@ -360,6 +365,9 @@ jobs:
     name: Triage
     needs: route
     if: needs.route.outputs.stage == 'triage'
+    concurrency:
+      group: fullsend-triage-${{ github.repository }}-${{ github.event.issue.number }}
+      cancel-in-progress: true
     # @v0 is hardcoded — GHA does not support expressions in uses:.
     # fullsend_ai_ref controls the ref for composite actions inside stage workflows.
     uses: fullsend-ai/fullsend/.github/workflows/reusable-triage.yml@v0
@@ -380,6 +388,9 @@ jobs:
     name: Code
     needs: route
     if: needs.route.outputs.stage == 'code'
+    concurrency:
+      group: fullsend-code-${{ github.repository }}-${{ github.event.issue.number }}
+      cancel-in-progress: true
     uses: fullsend-ai/fullsend/.github/workflows/reusable-code.yml@v0
     with:
       event_type: ${{ github.event_name }}
@@ -398,6 +409,9 @@ jobs:
     name: Review
     needs: route
     if: needs.route.outputs.stage == 'review'
+    concurrency:
+      group: fullsend-review-${{ github.repository }}-${{ github.event.pull_request.number || github.event.issue.number }}
+      cancel-in-progress: true
     uses: fullsend-ai/fullsend/.github/workflows/reusable-review.yml@v0
     with:
       event_type: ${{ github.event_name }}
@@ -416,6 +430,9 @@ jobs:
     name: Fix
     needs: route
     if: needs.route.outputs.stage == 'fix'
+    concurrency:
+      group: fullsend-fix-${{ github.repository }}-${{ github.event.pull_request.number || github.event.issue.number }}
+      cancel-in-progress: true
     uses: fullsend-ai/fullsend/.github/workflows/reusable-fix.yml@v0
     with:
       event_type: ${{ github.event_name }}
@@ -435,6 +452,9 @@ jobs:
     name: Retro
     needs: route
     if: needs.route.outputs.stage == 'retro'
+    concurrency:
+      group: fullsend-retro-${{ github.repository }}-${{ github.event.pull_request.number || github.event.issue.number }}
+      cancel-in-progress: true
     uses: fullsend-ai/fullsend/.github/workflows/reusable-retro.yml@v0
     with:
       event_type: ${{ github.event_name }}
@@ -453,6 +473,9 @@ jobs:
     name: Prioritize
     needs: route
     if: needs.route.outputs.stage == 'prioritize'
+    concurrency:
+      group: fullsend-prioritize-${{ github.repository }}-${{ github.event.issue.number }}
+      cancel-in-progress: true
     uses: fullsend-ai/fullsend/.github/workflows/reusable-prioritize.yml@v0
     with:
       event_type: ${{ github.event_name }}
diff --git a/.github/workflows/reusable-fix.yml b/.github/workflows/reusable-fix.yml
index 1f75a6c54..2f41130b3 100644
--- a/.github/workflows/reusable-fix.yml
+++ b/.github/workflows/reusable-fix.yml
@@ -1,5 +1,8 @@
-# Reusable fix agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable fix agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled).
 name: Fix Agent
 
 on:
@@ -51,6 +54,15 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: >-
+    fullsend-fix-agent-${{ inputs.source_repo }}-${{
+      fromJSON(inputs.event_payload).pull_request.number
+      || fromJSON(inputs.event_payload).issue.number
+      || inputs.pr_number
+    }}
+  cancel-in-progress: true
+
 jobs:
   fix:
     name: Fix
diff --git a/.github/workflows/reusable-prioritize.yml b/.github/workflows/reusable-prioritize.yml
index 8cfac73fb..a9216c833 100644
--- a/.github/workflows/reusable-prioritize.yml
+++ b/.github/workflows/reusable-prioritize.yml
@@ -1,5 +1,8 @@
-# Reusable prioritize agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable prioritize agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled).
 name: Prioritize Agent
 
 on:
@@ -43,6 +46,10 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: fullsend-prioritize-agent-${{ inputs.source_repo }}-${{ fromJSON(inputs.event_payload).issue.number }}
+  cancel-in-progress: true
+
 jobs:
   prioritize:
     name: Prioritize
diff --git a/.github/workflows/reusable-retro.yml b/.github/workflows/reusable-retro.yml
index 92edf04c1..05f86ad92 100644
--- a/.github/workflows/reusable-retro.yml
+++ b/.github/workflows/reusable-retro.yml
@@ -1,5 +1,8 @@
-# Reusable retro agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable retro agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled).
 name: Retro Agent
 
 on:
@@ -39,6 +42,10 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: fullsend-retro-agent-${{ inputs.source_repo }}-${{ fromJSON(inputs.event_payload).pull_request.number || fromJSON(inputs.event_payload).issue.number }}
+  cancel-in-progress: true
+
 jobs:
   retro:
     name: Retro
diff --git a/.github/workflows/reusable-review.yml b/.github/workflows/reusable-review.yml
index 2f3159fb1..02d4c4df7 100644
--- a/.github/workflows/reusable-review.yml
+++ b/.github/workflows/reusable-review.yml
@@ -1,5 +1,8 @@
-# Reusable review agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable review agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled).
 name: Review Agent
 
 on:
@@ -39,6 +42,10 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: fullsend-review-agent-${{ inputs.source_repo }}-${{ fromJSON(inputs.event_payload).pull_request.number || fromJSON(inputs.event_payload).issue.number }}
+  cancel-in-progress: true
+
 jobs:
   review:
     name: Review
diff --git a/.github/workflows/reusable-triage.yml b/.github/workflows/reusable-triage.yml
index af1dedbf6..52f4c982b 100644
--- a/.github/workflows/reusable-triage.yml
+++ b/.github/workflows/reusable-triage.yml
@@ -1,5 +1,9 @@
-# Reusable triage agent workflow. Called by thin callers in .fullsend repos
-# via workflow_call. Runs in the caller's repo context (secrets, checkout).
+# Reusable triage agent workflow. Called by dispatch workflows via workflow_call.
+# Runs in the caller's repo context (secrets, checkout).
+#
+# Concurrency: agent-scoped cancel-in-progress group (distinct from dispatch/thin
+# caller groups so workflow_call parent runs are not cancelled). Latest agent
+# run for an issue wins.
 name: Triage Agent
 
 on:
@@ -39,6 +43,10 @@ on:
       FULLSEND_GCP_PROJECT_ID:
         required: true
 
+concurrency:
+  group: fullsend-triage-agent-${{ inputs.source_repo }}-${{ fromJSON(inputs.event_payload).issue.number }}
+  cancel-in-progress: true
+
 jobs:
   triage:
     name: Triage
diff --git a/docs/ADRs/0034-centralized-shim-routing-via-dispatch.md b/docs/ADRs/0034-centralized-shim-routing-via-dispatch.md
index 6884b1c24..bff1351da 100644
--- a/docs/ADRs/0034-centralized-shim-routing-via-dispatch.md
+++ b/docs/ADRs/0034-centralized-shim-routing-via-dispatch.md
@@ -162,3 +162,8 @@ The `stage` input to `dispatch.yml` becomes optional. When provided
   the same routing script. Per-org shims could also adopt
   `reusable-fullsend.yml` directly, eliminating `dispatch.yml` as a
   routing layer entirely — see ADR 0033 Open Questions.
+
+## Implementation note (#981)
+
+Per-role dispatch concurrency is configured in repository workflows; the routing
+model in this ADR is unchanged.
diff --git a/docs/ADRs/0041-synchronous-workflow-call-event-dispatch.md b/docs/ADRs/0041-synchronous-workflow-call-event-dispatch.md
index 0d43276db..8b6ed9560 100644
--- a/docs/ADRs/0041-synchronous-workflow-call-event-dispatch.md
+++ b/docs/ADRs/0041-synchronous-workflow-call-event-dispatch.md
@@ -138,3 +138,8 @@ re-evaluate whether a discovery mechanism is needed.
   `needs:` / concurrency review ([#504](https://github.com/fullsend-ai/fullsend/issues/504)).
 - Discovery may be revisited after [ADR 0038](0038-universal-harness-access.md)
   agent architecture changes land.
+
+## Implementation note (#981)
+
+Per-repo concurrency follow-up ([#504](https://github.com/fullsend-ai/fullsend/issues/504))
+is addressed in workflow configuration; the dispatch shape in this ADR is unchanged.
diff --git a/internal/scaffold/fullsend-repo/templates/shim-per-repo.yaml b/internal/scaffold/fullsend-repo/templates/shim-per-repo.yaml
index d8c36fbda..0ce727435 100644
--- a/internal/scaffold/fullsend-repo/templates/shim-per-repo.yaml
+++ b/internal/scaffold/fullsend-repo/templates/shim-per-repo.yaml
@@ -13,6 +13,10 @@
 # which determines the stage and conditionally calls the appropriate
 # reusable-{stage}.yml workflow. Adding a new stage requires only a case
 # branch in reusable-dispatch.yml — zero changes to this repo.
+#
+# Concurrency: per-role cancel-in-progress groups live in reusable-dispatch.yml
+# stage jobs and agent-scoped groups on reusable-{stage}.yml — not on this shim.
+# A monolithic shim group would serialize unrelated roles and drop pending runs (#2452).
 name: fullsend
 
 permissions:
@@ -35,9 +39,6 @@ on:
 
 jobs:
   dispatch:
-    concurrency:
-      group: fullsend-dispatch-${{ github.event.issue.number || github.event.pull_request.number }}
-      cancel-in-progress: false
     if: >-
       github.event_name != 'issue_comment'
       || github.event.comment.user.type != 'Bot'
diff --git a/internal/scaffold/scaffold_test.go b/internal/scaffold/scaffold_test.go
index 0ca8f6c0d..6acaa564d 100644
--- a/internal/scaffold/scaffold_test.go
+++ b/internal/scaffold/scaffold_test.go
@@ -145,6 +145,21 @@ func TestShimWorkflowCallTemplateContent(t *testing.T) {
 	assert.NotContains(t, s, "curl")
 }
 
+func TestShimPerRepoTemplateContent(t *testing.T) {
+	content, err := FullsendRepoFile("templates/shim-per-repo.yaml")
+	require.NoError(t, err)
+	s := string(content)
+	assert.True(t, strings.HasPrefix(s, "---\n"), "per-repo shim must start with YAML document start marker")
+	assert.Contains(t, s, "dispatch:")
+	assert.Contains(t, s, "stop-fix:")
+	assert.Contains(t, s, "__REUSABLE_DISPATCH__")
+	assert.Contains(t, s, "install_mode: per-repo")
+	// Per-role concurrency lives in reusable-dispatch.yml, not a monolithic shim group (#2452).
+	assert.NotContains(t, s, "fullsend-dispatch-${{")
+	assert.NotContains(t, s, "concurrency:")
+	assert.Contains(t, s, "per-role cancel-in-progress groups live in reusable-dispatch.yml")
+}
+
 func TestShimTriggerParity(t *testing.T) {
 	// Both shim templates must declare the same event trigger types so that
 	// per-repo and workflow-call installation modes have identical behavior.
diff --git a/internal/scaffold/workflow_call_alignment_test.go b/internal/scaffold/workflow_call_alignment_test.go
index 0379396e7..756af0786 100644
--- a/internal/scaffold/workflow_call_alignment_test.go
+++ b/internal/scaffold/workflow_call_alignment_test.go
@@ -39,9 +39,107 @@ type callerWorkflow struct {
 }
 
 type callerJob struct {
-	Uses    string            `yaml:"uses"`
-	With    map[string]string `yaml:"with"`
-	Secrets map[string]string `yaml:"secrets"`
+	Uses        string            `yaml:"uses"`
+	With        map[string]string `yaml:"with"`
+	Secrets     map[string]string `yaml:"secrets"`
+	Concurrency *jobConcurrency   `yaml:"concurrency"`
+}
+
+type jobConcurrency struct {
+	Group            string `yaml:"group"`
+	CancelInProgress bool   `yaml:"cancel-in-progress"`
+}
+
+// reusableStageWorkflow includes workflow-level concurrency on reusable agent workflows.
+type reusableStageWorkflow struct {
+	Concurrency *jobConcurrency  `yaml:"concurrency"`
+	On          reusableWorkflow `yaml:"on"`
+}
+
+type stageConcurrencyExpectation struct {
+	groupPrefix string
+	groupMust   []string
+}
+
+var thinCallerConcurrencyExpectations = map[string]stageConcurrencyExpectation{
+	"triage": {
+		groupPrefix: "fullsend-triage-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+	"code": {
+		groupPrefix: "fullsend-code-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+	"review": {
+		groupPrefix: "fullsend-review-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number"},
+	},
+	"fix": {
+		groupPrefix: "fullsend-fix-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number", "inputs.pr_number"},
+	},
+	"retro": {
+		groupPrefix: "fullsend-retro-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number"},
+	},
+	"prioritize": {
+		groupPrefix: "fullsend-prioritize-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+}
+
+var reusableAgentConcurrencyExpectations = map[string]stageConcurrencyExpectation{
+	"triage": {
+		groupPrefix: "fullsend-triage-agent-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+	"code": {
+		groupPrefix: "fullsend-code-agent-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+	"review": {
+		groupPrefix: "fullsend-review-agent-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number"},
+	},
+	"fix": {
+		groupPrefix: "fullsend-fix-agent-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number", "inputs.pr_number"},
+	},
+	"retro": {
+		groupPrefix: "fullsend-retro-agent-",
+		groupMust:   []string{"inputs.source_repo", "pull_request.number", "issue.number"},
+	},
+	"prioritize": {
+		groupPrefix: "fullsend-prioritize-agent-",
+		groupMust:   []string{"inputs.source_repo", "issue.number"},
+	},
+}
+
+var dispatchStageConcurrencyExpectations = map[string]stageConcurrencyExpectation{
+	"triage": {
+		groupPrefix: "fullsend-triage-",
+		groupMust:   []string{"github.repository", "github.event.issue.number"},
+	},
+	"code": {
+		groupPrefix: "fullsend-code-",
+		groupMust:   []string{"github.repository", "github.event.issue.number"},
+	},
+	"review": {
+		groupPrefix: "fullsend-review-",
+		groupMust:   []string{"github.repository", "github.event.pull_request.number", "github.event.issue.number"},
+	},
+	"fix": {
+		groupPrefix: "fullsend-fix-",
+		groupMust:   []string{"github.repository", "github.event.pull_request.number", "github.event.issue.number"},
+	},
+	"retro": {
+		groupPrefix: "fullsend-retro-",
+		groupMust:   []string{"github.repository", "github.event.pull_request.number", "github.event.issue.number"},
+	},
+	"prioritize": {
+		groupPrefix: "fullsend-prioritize-",
+		groupMust:   []string{"github.repository", "github.event.issue.number"},
+	},
 }
 
 // reusableWorkflowRef extracts the reusable workflow filename from a uses: reference.
@@ -227,6 +325,83 @@ func TestReusableDispatchProjectNumberInput(t *testing.T) {
 		"prioritize job should thread project_number from dispatch inputs")
 }
 
+// TestReusableDispatchStageConcurrency validates per-role cancel-in-progress groups
+// on all stage jobs in reusable-dispatch.yml (#981, #982, ADR 0033).
+func TestReusableDispatchStageConcurrency(t *testing.T) {
+	content, err := os.ReadFile(filepath.Join("..", "..", ".github", "workflows", "reusable-dispatch.yml"))
+	require.NoError(t, err)
+
+	var caller callerWorkflow
+	require.NoError(t, yaml.Unmarshal(content, &caller))
+
+	for stage, expect := range dispatchStageConcurrencyExpectations {
+		t.Run(stage, func(t *testing.T) {
+			job, ok := caller.Jobs[stage]
+			require.True(t, ok, "job %q should exist", stage)
+			require.NotNil(t, job.Concurrency, "job %q should declare a concurrency group", stage)
+			assert.Contains(t, job.Concurrency.Group, expect.groupPrefix)
+			for _, fragment := range expect.groupMust {
+				assert.Contains(t, job.Concurrency.Group, fragment,
+					"job %q concurrency group should reference %q", stage, fragment)
+			}
+			assert.True(t, job.Concurrency.CancelInProgress,
+				"job %q should cancel in-progress runs when a newer dispatch arrives", stage)
+		})
+	}
+}
+
+// TestReusableAgentWorkflowConcurrency validates agent-scoped cancel-in-progress
+// groups on reusable stage workflows. Groups use a distinct -agent- prefix so
+// they do not collide with dispatch/thin-caller groups on workflow_call parents.
+func TestReusableAgentWorkflowConcurrency(t *testing.T) {
+	for stage, expect := range reusableAgentConcurrencyExpectations {
+		t.Run(stage, func(t *testing.T) {
+			path := filepath.Join("..", "..", ".github", "workflows", fmt.Sprintf("reusable-%s.yml", stage))
+			content, err := os.ReadFile(path)
+			require.NoError(t, err)
+
+			var wf reusableStageWorkflow
+			require.NoError(t, yaml.Unmarshal(content, &wf))
+			require.NotNil(t, wf.Concurrency, "reusable-%s.yml should declare workflow-level concurrency", stage)
+			assert.Contains(t, wf.Concurrency.Group, expect.groupPrefix)
+			for _, fragment := range expect.groupMust {
+				assert.Contains(t, wf.Concurrency.Group, fragment,
+					"reusable-%s.yml concurrency group should reference %q", stage, fragment)
+			}
+			assert.True(t, wf.Concurrency.CancelInProgress,
+				"reusable-%s.yml should cancel in-progress runs", stage)
+
+			callerExpect := thinCallerConcurrencyExpectations[stage]
+			assert.NotEqual(t, callerExpect.groupPrefix, expect.groupPrefix,
+				"reusable-%s.yml must use a distinct agent-scoped group prefix", stage)
+			assert.Contains(t, wf.Concurrency.Group, "-agent-",
+				"reusable-%s.yml group must be agent-scoped, not reuse dispatch/thin-caller prefix", stage)
+		})
+	}
+}
+
+// TestThinCallerStageConcurrency validates per-role cancel-in-progress groups on
+// per-org thin caller workflows in the scaffold (#981, ADR 0033).
+func TestThinCallerStageConcurrency(t *testing.T) {
+	for stage, expect := range thinCallerConcurrencyExpectations {
+		t.Run(stage, func(t *testing.T) {
+			path := fmt.Sprintf(".github/workflows/%s.yml", stage)
+			content := loadRenderedScaffoldCaller(path)(t)
+
+			var wf reusableStageWorkflow
+			require.NoError(t, yaml.Unmarshal(content, &wf))
+			require.NotNil(t, wf.Concurrency, "%s should declare workflow-level concurrency", path)
+			assert.Contains(t, wf.Concurrency.Group, expect.groupPrefix)
+			for _, fragment := range expect.groupMust {
+				assert.Contains(t, wf.Concurrency.Group, fragment,
+					"%s concurrency group should reference %q", path, fragment)
+			}
+			assert.True(t, wf.Concurrency.CancelInProgress,
+				"%s should cancel in-progress runs when a newer dispatch arrives", path)
+		})
+	}
+}
+
 // TestReusableDispatchUsesFullyQualifiedPaths validates that reusable-dispatch.yml
 // references stage workflows with fully-qualified paths, not relative (./) paths.
 // Relative paths resolve against the caller's repo, which breaks per-repo mode