diff --git a/aw_server/api.py b/aw_server/api.py
index a143c0c..3c672ed 100644
--- a/aw_server/api.py
+++ b/aw_server/api.py
@@ -107,7 +107,11 @@ def import_bucket(self, bucket_data: Any):
         bucket_id = bucket_data["id"]
         logger.info(f"Importing bucket {bucket_id}")
 
-        # TODO: Check that bucket doesn't already exist
+        if bucket_id in self.db.buckets():
+            raise Exception(
+                f"Bucket '{bucket_id}' already exists. Delete it first or rename the bucket before importing."
+            )
+
         self.db.create_bucket(
             bucket_id,
             type=bucket_data["type"],
@@ -132,8 +136,15 @@ def import_bucket(self, bucket_data: Any):
         )
 
     def import_all(self, buckets: Dict[str, Any]):
-        for bid, bucket in buckets.items():
-            self.import_bucket(bucket)
+        imported: List[str] = []
+        try:
+            for _bid, bucket in buckets.items():
+                self.import_bucket(bucket)
+                imported.append(bucket["id"])
+        except Exception:
+            for bid in imported:
+                self.db.delete_bucket(bid)
+            raise
 
     def create_bucket(
         self,
diff --git a/aw_server/rest.py b/aw_server/rest.py
index 5a6b822..1d3089c 100644
--- a/aw_server/rest.py
+++ b/aw_server/rest.py
@@ -370,18 +370,22 @@ class ImportAllResource(Resource):
     @api.expect(buckets_export)
     @copy_doc(ServerAPI.import_all)
     def post(self):
-        # If import comes from a form in th web-ui
-        if len(request.files) > 0:
-            # web-ui form only allows one file, but technically it's possible to
-            # upload multiple files at the same time
-            for filename, f in request.files.items():
-                buckets = json.loads(f.stream.read())["buckets"]
+        try:
+            # If import comes from a form in the web-ui
+            if len(request.files) > 0:
+                # web-ui form only allows one file, but technically it's possible to
+                # upload multiple files at the same time
+                for filename, f in request.files.items():
+                    buckets = json.loads(f.stream.read())["buckets"]
+                    current_app.api.import_all(buckets)
+            # Normal import from body
+            else:
+                buckets = request.get_json()["buckets"]
                 current_app.api.import_all(buckets)
-        # Normal import from body
-        else:
-            buckets = request.get_json()["buckets"]
-            current_app.api.import_all(buckets)
-        return None, 200
+        except Exception as e:
+            logger.exception("Import failed")
+            return {"message": str(e)}, 400
+        return {"message": "Import successful"}, 200
 
 
 # LOGGING