diff --git a/graphicswin.cpp b/graphicswin.cpp
index f8279fd5..0b1131c2 100644
--- a/graphicswin.cpp
+++ b/graphicswin.cpp
@@ -531,8 +531,8 @@ void GraphicsWindow::EnsureValidActives(void) {
 
     // And update the checked state for various menus
     bool locked = LockedInWorkplane();
-    CheckMenuById(MNU_FREE_IN_3D, !locked);
-    CheckMenuById(MNU_SEL_WORKPLANE, locked);
+    RadioMenuById(MNU_FREE_IN_3D, !locked);
+    RadioMenuById(MNU_SEL_WORKPLANE, locked);
 
     SS.UndoEnableMenus();
 
@@ -544,8 +544,8 @@ void GraphicsWindow::EnsureValidActives(void) {
             SS.viewUnits = SolveSpace::UNIT_MM;
             break;
     }
-    CheckMenuById(MNU_UNITS_MM, SS.viewUnits == SolveSpace::UNIT_MM);
-    CheckMenuById(MNU_UNITS_INCHES, SS.viewUnits == SolveSpace::UNIT_INCHES);
+    RadioMenuById(MNU_UNITS_MM, SS.viewUnits == SolveSpace::UNIT_MM);
+    RadioMenuById(MNU_UNITS_INCHES, SS.viewUnits == SolveSpace::UNIT_INCHES);
 
     ShowTextWindow(SS.GW.showTextWindow);
     CheckMenuById(MNU_SHOW_TEXT_WND, SS.GW.showTextWindow);
diff --git a/solvespace.h b/solvespace.h
index a5437fea..9a5c4633 100644
--- a/solvespace.h
+++ b/solvespace.h
@@ -128,7 +128,8 @@ void LoadAllFontFiles(void);
 void OpenWebsite(const char *url);
 
 void CheckMenuById(int id, BOOL checked);
-void EnableMenuById(int id, BOOL checked);
+void RadioMenuById(int id, BOOL selected);
+void EnableMenuById(int id, BOOL enabled);
 
 void ShowGraphicsEditControl(int x, int y, char *s);
 void HideGraphicsEditControl(void);
diff --git a/win32/w32main.cpp b/win32/w32main.cpp
index 471b1207..07293444 100644
--- a/win32/w32main.cpp
+++ b/win32/w32main.cpp
@@ -936,6 +936,11 @@ void CheckMenuById(int id, BOOL checked)
 {
     MenuById(id, checked, TRUE);
 }
+void RadioMenuById(int id, BOOL selected)
+{
+    // Windows does not natively support radio-button menu items
+    MenuById(id, selected, TRUE);
+}
 void EnableMenuById(int id, BOOL enabled)
 {
     MenuById(id, enabled, FALSE);