diff --git a/cypress/e2e/live-tracking/instruct-measure.cy.js b/cypress/e2e/live-tracking/instruct-measure.cy.js
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+/**
+ * Live Tracking — Instruct measure flow (issue #253)
+ *
+ * Verifies the approver flow for instructing a measure that the
+ * coordinator did not propose:
+ *   1. the approver opens the property drawer at the Measures section,
+ *   2. picks a measure from the canonical catalogue dropdown and submits,
+ *   3. the drawer reflects the new instructed measure (optimistic chip),
+ *   4. the POST hits the instructed-measures route which pushes
+ *      `instructed_measures` back to HubSpot,
+ *   5. the approval log surface shows a row for the new approval.
+ *
+ * Mirrors `halted-state.cy.js` / `domna-survey.cy.js`. The spec uses
+ * `cy.intercept` so the HubSpot push side-effect is observable without a
+ * real CRM round-trip.
+ */
+
+const PORTFOLIO_SLUG = Cypress.env("LIVE_PORTFOLIO_SLUG");
+const TARGET_DEAL_NAME = Cypress.env("LIVE_INSTRUCT_DEAL_NAME");
+const INSTRUCT_MEASURE = "Loft insulation";
+
+describe("Instruct measure — approver flow", function () {
+  before(function () {
+    if (!PORTFOLIO_SLUG) {
+      cy.log(
+        "LIVE_PORTFOLIO_SLUG env var not set — skipping live tracking specs",
+      );
+      this.skip();
+    }
+  });
+
+  function openDrawerForTargetDeal() {
+    cy.visit(`/portfolio/${PORTFOLIO_SLUG}/your-projects/live`);
+
+    // Switch to the Measures tab — the easiest way into the drawer at the
+    // Measures section.
+    cy.contains("button, [role=tab]", "Measures").click();
+
+    if (TARGET_DEAL_NAME) {
+      cy.contains("[data-testid=measures-row]", TARGET_DEAL_NAME).click();
+    } else {
+      cy.get("[data-testid=measures-row]").first().click();
+    }
+
+    cy.get("[data-testid=property-detail-drawer]").should("be.visible");
+    cy.get("[data-testid=drawer-section-measures]").should("exist");
+  }
+
+  it("lets an approver instruct a measure and reflects it in the drawer + approval log", () => {
+    // Capture the API call so we can assert the payload that would be
+    // pushed to HubSpot under `instructed_measures`.
+    cy.intercept(
+      "POST",
+      `/api/portfolio/*/instructed-measures`,
+    ).as("instructMeasure");
+
+    openDrawerForTargetDeal();
+
+    // Approver-only form is visible at the bottom of the Measures section.
+    cy.get("[data-testid=instruct-measure-select]").should("be.visible");
+
+    cy.get("[data-testid=instruct-measure-select]").select(INSTRUCT_MEASURE);
+    cy.get("[data-testid=instruct-measure-submit]")
+      .should("not.be.disabled")
+      .click();
+
+    // Wait for the POST to land and assert the body shape that the
+    // service uses to drive the HubSpot push.
+    cy.wait("@instructMeasure").then((intercepted) => {
+      expect(intercepted.request.body).to.deep.include({
+        measureName: INSTRUCT_MEASURE,
+      });
+      // Response from our route signals the HubSpot sync outcome — it is
+      // either "ok" (mock recorded the push) or "failed" (network error).
+      // We accept either here so the spec stays portable across envs.
+      expect(intercepted.response.statusCode).to.be.oneOf([200, 201]);
+      expect(intercepted.response.body).to.have.property("ok", true);
+      expect(intercepted.response.body).to.have.property("hubspotSync");
+    });
+
+    // Drawer reflects the instructed measure as an optimistic chip.
+    cy.get("[data-testid=instructed-measures-list]").should("be.visible");
+    cy.get("[data-testid=instructed-measure-chip]")
+      .should("contain.text", INSTRUCT_MEASURE);
+
+    // No error banner.
+    cy.get("[data-testid=instruct-measure-error]").should("not.exist");
+
+    // Approval log section reveals the new approval row when expanded.
+    cy.contains("Approval Log").click();
+    cy.contains(INSTRUCT_MEASURE).should("exist");
+  });
+});