Drupal Alignment screwed up in IE but works great in FF

I have designed a si开发者_开发百科te for my team using drupal and it works and looks great in FF but when i open it in IE the page looks as if it is murdered by someone. The alignment is screwed up totally. What can i do to fix it.

You can make an IE style sheet and include it using conditional styles:

<!--[if IE]>
  add stylesheet here.
<![endif]-->

If you are using a subtheme of zen, you can use conditional styles in your .info file:

conditional-stylesheets[if IE][all][] = css/ie.css

Update:
You also need to remember to compress your css files, since Drupal usually will use more css files than IE can handle with css optimization is disabled. This in turn, will require you to clear the cache a lot.