Subtilisin is the most extensively studied model system for protein engineering. The primary motivating factor for the interest in subtilisin is the commercial utility of this class of proteases. The subtilisin symposium was the first international meeting to bring together a large number of groups that have focused on the subtilisins and the subtilases-the protein superfamily of subtilisin-like enzymes. The results presented at the symposium are in this way a unique compendium of a broad spectrum of work largely focused on harnessing the potential of site-directed mutagenesis to understand...