I'm a relative newbie to this. See my website http://www.ozemail.com.au/~russwilson you'll notice it uses Lefteris menu system. That includes some things not commonly supported in the W3C DTDs (Body marginheight, e.g.). What need to know is (i) do the browsers make use of the doctype statement; (ii) for validation purposes (e.g., W3C) can I create my own and store it on my ISP server (my ISP server is a basic storage system, no programming available with the standard plan, so ... will the html files "read" a custom DTD stored on such a server, like they would read a .css file? (iii) does anyone know of pre-written DTDs; (iv) why doesn't HD6 allow syntax editing for its internal validation system; (v) what is the "TidyTool" I've seen mentioned.