The following image describes the UI for a sidebar that would allow simpler navigation through a project. Sidebars are very common in Mac applications, especially OS X Leopard applications. Apple uses sidebars in many of their applications including the Finder, iPhoto, and iTunes.

I’ve left out any icons that would go next to the list items, but the final application would probably do well to include icons next to list items since this is the common form for sidebar items.