ExpressionEngine doesn't have themes like Wordpress or Drupal has. It's templating system is a little different. It's still all HTML / CSS though. Here is wh

ExpressionEngine doesn't have themes like Wordpress or Drupal has. It's templating system is a little different. It's still all HTML / CSS though. Here is what I would do. First have your designers create PSD mock-ups for their designs. Then, pick the winning design(s) and either have those designers build HTML / CSS from it or have someone else do this. Lastly, hire a guru of your chosen CMS to build that HTML / CSS into themes / templates.