diff --git a/SketchWidget.py b/SketchWidget.py
index 31bba54..c719dde 100644
--- a/SketchWidget.py
+++ b/SketchWidget.py
@@ -225,12 +225,16 @@ class SketchWidget:
         if event.button == 1:
             if self.mode == 'line':
                 self.do_line_left_click(event.x, event.y)
+            elif self.mode == 'circle':
+                self.do_circle_left_click(event.x, event.y)
         elif event.button == 2:
             self.panning = True
             self.panning_start = (event.x, self.size[1] - event.y)
         elif event.button == 3:
             if self.mode == 'line':
                 self.do_line_right_click(event.x, event.y)
+            elif self.mode == 'circle':
+                self.do_circle_right_click(event.x, event.y)
 
     def button_release_event(self, widget, event, data = None):
         if event.button == 2:
@@ -381,3 +385,14 @@ class SketchWidget:
             # cancel line currently being drawn
             self.drawingLine = None
             self.queue_redraw()
+
+    def do_circle_left_click(self, x, y):
+        pt = self.screenPtToPt((x, self.size[1] - y))
+        if self.drawingCircle is None:
+            self.drawingCircle = Circle(pt[0], pt[1], 0)
+
+    def do_circle_right_click(self, x, y):
+        if self.drawingCircle is not None:
+            # cancel circle currently being drawn
+            self.drawingCircle = None
+            self.queue_redraw()