diff --git a/package-lock.json b/package-lock.json
index dba6b98..58373a2 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "mrvn-cli",
-  "version": "0.6.1",
+  "version": "0.7.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "mrvn-cli",
-      "version": "0.6.1",
+      "version": "0.7.1",
       "license": "MIT",
       "dependencies": {
         "@anthropic-ai/claude-agent-sdk": "^0.2.37",
diff --git a/package.json b/package.json
index 685d0c5..90281f5 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mrvn-cli",
-  "version": "0.7.0",
+  "version": "0.7.1",
   "description": "AI-powered software product development assistant with Product Owner, Delivery Manager, and Technical Lead personas",
   "type": "module",
   "bin": {
diff --git a/test/methodology/drift-check.test.ts b/test/methodology/drift-check.test.ts
new file mode 100644
index 0000000..f8ba93a
--- /dev/null
+++ b/test/methodology/drift-check.test.ts
@@ -0,0 +1,164 @@
+/**
+ * AC1.4 — Drift check between concept registry and persona guidance.
+ *
+ * Validates that the methodology knowledge encoded in persona guidance
+ * (DM system prompt, SAP AEM plugin fragments) stays in sync with the
+ * concept registry. If a concept registry entry diverges from the prose
+ * that originally seeded it, these tests fail — forcing a reconciliation
+ * before merge.
+ *
+ * Tests use keyword matching (not exact phrases) because registry items
+ * are structured labels while persona guidance is prose.
+ */
+import { describe, it, expect, beforeAll } from "vitest";
+import { deliveryManager } from "../../src/personas/builtin/delivery-manager.js";
+import { sapAemPlugin } from "../../src/plugins/builtin/sap-aem.js";
+import { getConceptRegistry } from "../../src/methodology/registry.js";
+
+const registry = getConceptRegistry();
+let dmPrompt: string;
+let aemDmFragment: string;
+let aemWildcardFragment: string;
+
+/** Extract significant keywords from a phrase (drops short filler words). */
+function keywords(phrase: string): string[] {
+  const stopWords = new Set(["to", "of", "the", "a", "an", "and", "or", "for", "in", "on", "with"]);
+  return phrase
+    .toLowerCase()
+    .split(/[\s,/]+/)
+    .filter((w) => w.length > 2 && !stopWords.has(w));
+}
+
+/** Check that most keywords from a phrase appear in the text. */
+function hasKeywordOverlap(text: string, phrase: string, minRatio = 0.5): boolean {
+  const kw = keywords(phrase);
+  if (kw.length === 0) return true;
+  const matched = kw.filter((w) => text.includes(w));
+  return matched.length / kw.length >= minRatio;
+}
+
+describe("Concept registry ↔ persona guidance drift check", () => {
+  beforeAll(() => {
+    dmPrompt = deliveryManager.systemPrompt.toLowerCase();
+
+    expect(sapAemPlugin.promptFragments).toBeDefined();
+    expect(sapAemPlugin.promptFragments!["delivery-manager"]).toBeDefined();
+    expect(sapAemPlugin.promptFragments!["*"]).toBeDefined();
+
+    aemDmFragment = sapAemPlugin.promptFragments!["delivery-manager"].toLowerCase();
+    aemWildcardFragment = sapAemPlugin.promptFragments!["*"].toLowerCase();
+  });
+
+  describe("Sprint 0 checklist vs DM persona guidance", () => {
+    const sprint0 = registry.get("sprint-0")!;
+
+    it("sprint-0 concept exists in registry", () => {
+      expect(sprint0).toBeDefined();
+    });
+
+    it("DM persona mentions Sprint 0 as variable-duration bootstrapping", () => {
+      expect(dmPrompt).toContain("sprint 0");
+      expect(dmPrompt).toContain("variable-duration");
+      expect(dmPrompt).toContain("bootstrapping");
+    });
+
+    it("DM persona states Sprint 0 exit criteria", () => {
+      expect(dmPrompt).toContain("ready to start sprint 1");
+    });
+
+    const genericCategories = sprint0.checklist!.filter((c) => !c.appliesWhen);
+
+    it("registry has the same number of generic checklist categories as DM persona sections", () => {
+      // DM persona has 4 bullet groups under Sprint 0: Infrastructure, Backlog, Ceremony, Integration
+      expect(genericCategories.length).toBe(4);
+    });
+
+    for (const section of genericCategories) {
+      it(`DM persona covers category "${section.category}" (keyword match)`, () => {
+        const matchedItems = section.items.filter((item) => hasKeywordOverlap(dmPrompt, item));
+        expect(matchedItems.length).toBeGreaterThan(
+          0,
+          `No items from "${section.category}" found in DM persona guidance. Items: ${section.items.join(", ")}`,
+        );
+      });
+
+      for (const item of section.items) {
+        it(`DM persona covers "${item}" from ${section.category}`, () => {
+          expect(hasKeywordOverlap(dmPrompt, item)).toBe(true);
+        });
+      }
+    }
+  });
+
+  describe("AEM addendum vs SAP AEM DM plugin fragment", () => {
+    const sprint0 = registry.get("sprint-0")!;
+    const aemAddendum = sprint0.checklist!.find((c) => c.appliesWhen === "methodology=aem");
+
+    it("AEM addendum section exists in registry", () => {
+      expect(aemAddendum).toBeDefined();
+    });
+
+    it("SAP AEM DM fragment mentions Sprint 0 for AEM", () => {
+      expect(aemDmFragment).toContain("sprint 0");
+    });
+
+    for (const item of aemAddendum!.items) {
+      it(`SAP AEM DM fragment covers "${item}" (keyword match)`, () => {
+        expect(hasKeywordOverlap(aemDmFragment, item)).toBe(true);
+      });
+    }
+  });
+
+  describe("AEM phases vs SAP AEM plugin wildcard fragment", () => {
+    const phaseIds = ["assess-use-case", "assess-technology", "define-solution"];
+
+    for (const phaseId of phaseIds) {
+      const phase = registry.get(phaseId);
+
+      it(`phase "${phaseId}" exists in registry`, () => {
+        expect(phase).toBeDefined();
+      });
+
+      it(`SAP AEM wildcard fragment covers phase "${phase!.name}" (keyword match)`, () => {
+        expect(hasKeywordOverlap(aemWildcardFragment, phase!.name)).toBe(true);
+      });
+    }
+
+    it("SAP AEM wildcard fragment describes the 3-phase approach", () => {
+      expect(aemWildcardFragment).toContain("3-phase");
+    });
+  });
+
+  describe("AEM document types vs registry artifact-type concepts", () => {
+    const aemOnlyTypes = ["use-case", "tech-assessment", "extension-design"];
+
+    for (const typeId of aemOnlyTypes) {
+      const concept = registry.get(typeId);
+
+      it(`artifact-type "${typeId}" exists in registry as AEM-scoped`, () => {
+        expect(concept).toBeDefined();
+        expect(concept!.category).toBe("artifact-type");
+        expect(concept!.methodology).toContain("aem");
+      });
+
+      it(`SAP AEM wildcard fragment mentions "${concept!.name}"`, () => {
+        expect(aemWildcardFragment).toContain(concept!.name.toLowerCase());
+      });
+    }
+  });
+
+  describe("Persona roles vs registry role concepts", () => {
+    const roles = ["product-owner", "delivery-manager", "tech-lead"];
+
+    for (const roleId of roles) {
+      const concept = registry.get(roleId);
+
+      it(`role "${roleId}" exists in registry for both methodologies`, () => {
+        expect(concept).toBeDefined();
+        expect(concept!.category).toBe("role");
+        expect(concept!.methodology).toContain("generic-agile");
+        expect(concept!.methodology).toContain("aem");
+      });
+    }
+  });
+});