diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index 818e60ec..bed40c4c 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -32,7 +32,7 @@ $ npm run build:prd
 ### Running dashboard server
 
 ```
-$ pip install .
+$ pip install -e .
 $ optuna-dashboard sqlite:///db.sqlite3
 ```