The mark-up and CSS are not valid. It fails basic WAI and 508 accessibility standards checks. It breaks if images are off but CSS is on. It breaks if JS is blocked or unsupported.
One of the most basic and obvious mistakes that relate to two of these issues is an anchor background colour that matches (rather than contrasts to) the anchor text colour.
It lacks white space, which makes it cramped. That HTMl form, for which fm has rightly been critical, does not even have a title. That is SEO 101, so back to school methinks! "Our Services" is positioned and styled as a link, but is not: that is a basic UX (usability experience) error.
As fm pointed out, why the inaccessible JS banner? Where is your H1 text? Why is "Corporate Services" a span instead of an H2 (which would follow on from an H1)?