diff --git a/app/__init__.py b/app/__init__.py
index 339362561..05ac4c0e7 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -301,15 +301,44 @@ def init_app(app):
         g.start = monotonic()
         g.endpoint = request.endpoint
 
+    @app.before_request
+    def handle_options():
+        if request.method == "OPTIONS":
+            response = make_response("", 204)
+            response.headers["Access-Control-Allow-Origin"] = "*"
+            response.headers["Access-Control-Allow-Methods"] = (
+                "GET, POST, PUT, DELETE, OPTIONS"
+            )
+            response.headers["Access-Control-Allow-Headers"] = (
+                "Content-Type, Authorization"
+            )
+            response.headers["Access-Control-Max-Age"] = "3600"
+            return response
+
     @app.after_request
     def after_request(response):
+        # Security headers for government compliance
         response.headers.add("X-Content-Type-Options", "nosniff")
+        response.headers.add("X-Frame-Options", "DENY")
+        response.headers.add("X-XSS-Protection", "1; mode=block")
+        response.headers.add("Referrer-Policy", "strict-origin-when-cross-origin")
+        response.headers.add(
+            "Permissions-Policy", "geolocation=(), microphone=(), camera=()"
+        )
 
-        # Some dynamic scan findings
+        # CORS-related security headers
         response.headers.add("Cross-Origin-Opener-Policy", "same-origin")
         response.headers.add("Cross-Origin-Embedder-Policy", "require-corp")
         response.headers.add("Cross-Origin-Resource-Policy", "same-origin")
-        response.headers.add("Cross-Origin-Opener-Policy", "same-origin")
+
+        if not request.path.startswith("/docs"):
+            response.headers.add(
+                "Content-Security-Policy", "default-src 'none'; frame-ancestors 'none';"
+            )
+
+        response.headers.add(
+            "Strict-Transport-Security", "max-age=31536000; includeSubDomains"
+        )
 
         return response
 
diff --git a/app/status/healthcheck.py b/app/status/healthcheck.py
index 012be880c..648c4225f 100644
--- a/app/status/healthcheck.py
+++ b/app/status/healthcheck.py
@@ -14,17 +14,20 @@ status = Blueprint("status", __name__)
 def show_status():
     try:
         if request.args.get("simple", None):
-            return jsonify(status="ok"), 200
+            response = jsonify(status="ok")
         else:
-            return (
-                jsonify(
-                    status="ok",  # This should be considered part of the public API
-                    git_commit=version.__git_commit__,
-                    build_time=version.__time__,
-                    db_version=get_db_version(),
-                ),
-                200,
+            response = jsonify(
+                status="ok",  # This should be considered part of the public API
+                git_commit=version.__git_commit__,
+                build_time=version.__time__,
+                db_version=get_db_version(),
             )
+
+        response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
+        response.headers["Pragma"] = "no-cache"
+        response.headers["Expires"] = "0"
+
+        return response, 200
     except Exception as e:
         current_app.logger.error(
             f"Unexpected error in show_status: {str(e)}", exc_info=True
@@ -36,13 +39,16 @@ def show_status():
 @status.route("/_status/live-service-and-organization-counts")
 def live_service_and_organization_counts():
     try:
-        return (
-            jsonify(
-                organizations=dao_count_organizations_with_live_services(),
-                services=dao_count_live_services(),
-            ),
-            200,
+        response = jsonify(
+            organizations=dao_count_organizations_with_live_services(),
+            services=dao_count_live_services(),
         )
+
+        response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
+        response.headers["Pragma"] = "no-cache"
+        response.headers["Expires"] = "0"
+
+        return response, 200
     except Exception as e:
         current_app.logger.error(
             f"Unexpected error in live_service_and_organization_counts: {str(e)}",
diff --git a/notifications_python_client/base.py b/notifications_python_client/base.py
index 9e1f7615a..ba6038fa6 100644
--- a/notifications_python_client/base.py
+++ b/notifications_python_client/base.py
@@ -23,9 +23,7 @@ class BaseAPIClient:
     This class is not thread-safe.
     """
 
-    def __init__(
-        self, api_key, base_url=API_HOST_NAME, timeout=30
-    ):
+    def __init__(self, api_key, base_url=API_HOST_NAME, timeout=30):
         """
         Initialise the client
         Error if either of base_url or secret missing
diff --git a/tests/app/test_security_headers.py b/tests/app/test_security_headers.py
new file mode 100644
index 000000000..c96ce9fac
--- /dev/null
+++ b/tests/app/test_security_headers.py
@@ -0,0 +1,30 @@
+import pytest
+
+
+@pytest.mark.usefixtures('notify_db_session')
+class TestSecurityHeaders:
+    """Test security headers for ZAP scan compliance."""
+
+    def test_options_request_returns_204_with_cors_headers(self, client):
+        """Test that OPTIONS requests return 204 with proper CORS headers."""
+        response = client.options('/')
+
+        assert response.status_code == 204
+        assert response.headers.get('Access-Control-Allow-Origin') == '*'
+        assert response.headers.get('Access-Control-Allow-Methods') == 'GET, POST, PUT, DELETE, OPTIONS'
+        assert response.headers.get('Access-Control-Allow-Headers') == 'Content-Type, Authorization'
+        assert response.headers.get('Access-Control-Max-Age') == '3600'
+
+    @pytest.mark.parametrize("endpoint", [
+        '/_status',
+        '/_status?simple=1',
+        '/_status/live-service-and-organization-counts'
+    ])
+    def test_status_endpoints_have_cache_control_headers(self, client, endpoint):
+        """Test that all status endpoints have proper cache-control headers."""
+        response = client.get(endpoint)
+
+        assert response.status_code == 200
+        assert response.headers.get('Cache-Control') == 'no-cache, no-store, must-revalidate'
+        assert response.headers.get('Pragma') == 'no-cache'
+        assert response.headers.get('Expires') == '0'