A recent trend in many organizations is the increasing acceptance of teleworking. The so-called groupware applications play an important role in the field of teleworking. These applications, based on networking, support collaboration of geographically remote people by means of advanced computer technologies. Collaborative Virtual Environments can be used for the development of groupware applications. To support collaboration in shared virtual environments, communication primitives and special purpose virtual objects are introduced. The latter are dynamic objects which can be manipulated by the users and support decision making. Manipulatable spreadsheets are introduced and demonstrated in a Business Game as an example of a Collaborative Virtual Environment.