diff --git a/src/actions.cpp b/src/actions.cpp
index 94ce544..efb961f 100644
--- a/src/actions.cpp
+++ b/src/actions.cpp
@@ -34,6 +34,9 @@
 #define REAPERAPI_MINIMAL
 #define REAPERAPI_WANT_CountSelectedTracks
 #define REAPERAPI_WANT_GetSelectedTrack
+#define REAPERAPI_WANT_EnumProjects
+#define REAPERAPI_WANT_Main_SaveProject
+#define REAPERAPI_WANT_ShowConsoleMsg
 #include "reaper_plugin_functions.h"
 
 namespace reasampler {
@@ -115,8 +118,44 @@ void reapplyActiveMode() {
 // state. Called after every state-changing Design View action so the view model
 // is not lost across save/close/reopen. Marking the project dirty is correct —
 // a Design View mutation is a project-level change the user should be prompted
-// to save. Safe when there is no active/saved project (saveToActiveProject no-ops).
+// to save.
+//
+// When the membership index is non-empty AND the project is unsaved, we prompt
+// the user to Save-As before persisting — mirroring the flow capture uses.
+// Gate: if membership is empty (no tracks tagged), skip the prompt entirely;
+// saveToActiveProject will no-op for an unsaved project, which is correct.
+//
+// DAW-ONLY ASSUMPTION: Main_SaveProject(proj, true) opens a Save-As dialog and
+// blocks until the user dismisses it. The blocking behaviour and dialog
+// appearance can only be confirmed in a running REAPER (same caveat as capture).
 void persistViewState() {
+    if (!g_session->view().membership().empty()) {
+        // At least one track is tagged — worth persisting. Check whether the
+        // project is saved and, if not, prompt Save-As so saveToActiveProject
+        // can write ext state. Mirrors capture's readRppPath idiom exactly.
+        ReaProject* proj = EnumProjects(-1, nullptr, 0);
+        if (proj) {
+            auto readRppPath = [&]() -> std::string {
+                std::vector<char> buf(4096, '\0');
+                EnumProjects(-1, buf.data(), static_cast<int>(buf.size()));
+                return std::string(buf.data());
+            };
+
+            if (readRppPath().empty()) {
+                // Project is unsaved — prompt Save-As.
+                Main_SaveProject(proj, true);
+                // Re-read: still empty means the user cancelled.
+                if (readRppPath().empty()) {
+                    ShowConsoleMsg(
+                        "ReaSampler: Design View state will not persist until "
+                        "the project is saved.\n");
+                    // The in-session tag state is left as-is — the mode change
+                    // already applied and remains valid for this session.
+                    return;
+                }
+            }
+        }
+    }
     g_session->saveToActiveProject();
 }