How do you work with Developers / Designers

When I am doing application development with Flash the work-flow usually consists of:

  • I spec out the app (with input from the design)
  • I develop the app.
  • Once the app is functioning, I pass it on to the designer to complete the UI and look and feel.
  • I make minor bug fixes and changes, but usually no UI changes

What is your work flow like? As a developer, when do you pass the work to the designer? Or if you are a designer, when do you start to work on the project?