This is Daleri Structure, a free XHTML/CSS design in the "Daleri" website template series by Andreas Viklund. The template was created with categorized content in mind, and it provides site owners with a number of different ways to organize the site structure.
The main navigation is created with definition lists, and the menu can be expanded to contain more links if needed. You can also use the main menu as an overview or a basic sitemap, and expand the site with subpages using the sidebar buttons or regular link lists. On sites with fewer pages, the definition list menu can be removed and replaced with an ad banner (600px wide) or a large logo. You can also place a horizontal text link menu in the the gray space between the header and the content, just to give another example. Feel free to experiment with the spaces to find your own preferred structure.
Template copyright and usage rights
Like all my XHTML/CSS templates, this template is completely free to download, free to use and free to modify in any way you may want to - without any limitations or obligations. I kindly ask you to keep the original design credits and the link to my website in the footer since it is a good way to support my template design work, but it is no requirement.
If you find this template useful, then I would recommend visiting my website every now and then, as you will be able to find more free templates there, along with useful tools and services that make it even easier to build complete, high-quality websites using website templates as starting points.
Professional template customization services are available. Contact me for rates and availability.