When I ordered these pants I ordered the size that I typically wear.  I was comfortable that they would work because if anything my other IZOD pants ran slightly large not small.  Imagine my surprise when my new pants fit only slightly looser than a wetsuit!  Simply put, not a pretty sight.  However, since the pants were exactly what I was looking for (mid-weight, casual, but not overly so) I decided to order a new pair one size up.  Guess what; just slightly loose, like my typical IZOD pants.  I would recommend ordering these larger rather than smaller if you have any concerns.  Otherwise, nice pants at a good price.