diff --git a/Running-Mastodon/Development-guide.md b/Running-Mastodon/Development-guide.md
index b288ec32..08ab9567 100644
--- a/Running-Mastodon/Development-guide.md
+++ b/Running-Mastodon/Development-guide.md
@@ -66,7 +66,7 @@ These are self-contained instructions for setting up a development environment o
 - Get [Xcode](https://developer.apple.com/xcode/) Command Line Tools:
 
 	```
-	xcode-select install
+	xcode-select --install
 	```
 
 - Get [Homebrew](https://brew.sh) and use it to install the other dependencies: