diff --git a/pyrobosim/pyrobosim/navigation/path_planner.py b/pyrobosim/pyrobosim/navigation/path_planner.py
index 5c1b90bd..0e0168f8 100644
--- a/pyrobosim/pyrobosim/navigation/path_planner.py
+++ b/pyrobosim/pyrobosim/navigation/path_planner.py
@@ -34,7 +34,11 @@ def __init__(self, planner_type, **planner_config):
             )
             return None
         if not planner_config:
-            planner_config = {}
+            warnings.warn(
+                f"No planner configuration provided. Must provide either a World or OccupancyGrid object.",
+                UserWarning,
+            )
+            return None
 
         self.planner_type = planner_type
         self.planner_config = planner_config