The number of endusers using the Internet increases on the inside and outside of offices. Enduser-initiative development of applications has become important for automation of their own tasks. As the solution by software reuse technology, this paper describes an Java-base application framework of the distributed systems such as the MOON (multi-organizational office network) systems for window work in banks, city offices, mail-order companies, etc. based on the philosophy : "All routine work both at office and at home should be carried out by computers." The application framework includes a common protocol for application forms and is composed of subframeworks corresponding to the three kinds of parts of client terminals, server-at-windows and the MOON servers. With respect to the problem of how to customize the application framework in the way of enduser-initiative development, two types of customization are given, namely, plug-in components and property definitions. Then do...