Answer - It depends on your definition of "support." If you are interested in those browsers which makes some attempt at supporting CSS, no matter how partial or bug-ridden, then the list is: * Internet Explorer 3.0 and above * Navigator 4.0 and above * Opera 3.6 and above * Konqueror * Arena * Emacs-w3 * Amaya * Lexicon * XPublish by Media Design in·Progress If instead you're interested in those browsers which are known to do a credible job of bug-free and mostly completel support for CSS1, then the list narrows somewhat dramatically: * Internet Explorer 5.0 for Macintosh and above * Internet Exporer 5.5 for Windows and above * Netscape Navigator 6.0 and above * Opera 4.0 and above While none of these browser can be claimed to have a perfect implementation of CSS1, they are all quite good and can be relied upon to operate in a consistent fashion for most of CSS1.