The paper reports on three projects at our laboratory that deal respectively with synchronous collaborative design, asynchronous collaborative design, and design coordination. The Electronic Cocktail Napkin and its mobile extension that runs on hand-held computers supports synchronous design with shared freehand drawing environments. The PHIDIAS hypermedia system supports long-term, asynchronous collaboration by enabling designers of large complex artifacts to store and retrieve rationale about design decisions and the Construction Kit Builder (CKB) supports team design by supporting a priori agreements among team members to avoid conflicts.