Macintosh Operating System 7

Finder Enhancements
Apple Computer, Inc. -- 1990
Bill contributed significant enhancements to the Mac OS desktop user interface.

Personal Filesharing
Apple Computer, Inc. -- 1990
Bill makes a last-minute rescue of the user interface, soothes hurt feelings, and establishes user interface precedents that continue to be followed today.

Inter-Application Communication
Apple Computer, Inc. -- 1990
Bill plugs a major security hole, integrates all remote access into a unified user interface, and anticipates some of the extended functionality now in MacOS X.