How do you make sure that div layers are positioned in the same place in IE and Firefox?

I'm having some difficulties making my site cross-browser compatible ... the divs are a bit messed up in IE, and when i try to fix that, it messes it up in Firefox. Very frustrating.

How do you make sure that div layers are positioned in the same place in IE and Firefox?windows xp sp2

Ahh yes, the unending cross-browser question. What you want to do is have your page detect which browser is being used to view your site by using javascript and then have it dynamically load the proper style sheet.

How do you make sure that div layers are positioned in the same place in IE and Firefox?microsoft sql server internet explorer

Welcome to the world of supposed DOM compliant browsers.

Neither IE nor Firefox adhere to what is specified by the W3C, so good luck getting it all to work the same.
IE is the cause of many grey hairs with web designers. What looks good in Firefox and Opera, IE tears apart.

The best thing to do is design it so it looks good in Firefox, then make very small changes and keep reviewing it in both IE and Firefox until they both render the divs correctly.

I ran into the same problem before and there really is no quick fix, unless you want to just start the whole thing over from scratch.
Use fixed size tables with absolute dimensions (not relative dimensions) and place your page components how you would want them to appear. Different browsers will 99.9% of the time display absolute sized tables as you intend for them to apear.