Kent Beck, Apple Computer, Inc. Ward Cunningham, Tektronix, Inc. Technical Report No. CR-87-43 September 17, 1987 Submitted to the OOPSLA-87 workshop on the Specification and Design for Object-Oriented Programming. Abstract We outline our adaptation of Pattern Language to object-oriented programming. We sumarize a system of five patterns we have successfuly used for designing window-based user int