diff --git a/itkwidgets/_initialization_params.py b/itkwidgets/_initialization_params.py
index 3ff6272f..99ae4df4 100644
--- a/itkwidgets/_initialization_params.py
+++ b/itkwidgets/_initialization_params.py
@@ -60,6 +60,7 @@ def build_config(ui=None):
     else:
         config = {}
     config['maxConcurrency'] = os.cpu_count() * 2
+    config['showSaveRoiButton'] = True
 
     return config
 
diff --git a/itkwidgets/viewer.py b/itkwidgets/viewer.py
index 106b3dbe..6c0ad375 100644
--- a/itkwidgets/viewer.py
+++ b/itkwidgets/viewer.py
@@ -82,6 +82,9 @@ async def run(self, ctx):
                 itk_viewer.registerEventListener(
                     'screenshotTaken', self.update_screenshot
                 )
+                itk_viewer.registerEventListener(
+                    'saveRoi', self.save_roi
+                )
                 # Once the viewer has been created any queued requests can be run
                 CellWatcher().update_viewer_status(self.parent)
                 asyncio.get_running_loop().call_soon_threadsafe(self.viewer_event.set)
@@ -124,6 +127,9 @@ def update_screenshot(self, base64_image):
                 </script>
             ''')
         self.img.display(html)
+    
+    def save_roi(self, roi):
+        api.log(f'save roi {roi}')
 
     def set_event(self, event_data):
         # Once the data has been set the deferred queue requests can be run