Can't see standalone in aspect ratio drop down

I’m following the Unity Game Development Essentials book and have reached a part in the tutorial where it’s asked me to set the aspect ratio drop down in the game view to Standalone (1024x768). Problem is I can’t see this in the dropdown, only web, free aspect and the other ratios (4:3, etc.). Are there some other settings elsewhere I need to enable Standalone in here?

Cheers

In Unity 3, you only get Standalone as an option if the build settings are set to Standalone.

–Eric