This document is a rough specification of proposed additions to XCCS, the internal character set of Interlisp and various other Xerox products and the direct ancestor of Unicode. Since no one else is maintaining it, the Medley Project has taken over the effort. The initial objective here is to be able to make use of more modern fonts, for which we need full XCCS-to-Unicode mappings, and to be able to handle the most important characters required to write modern languages.