Abstract The rapidly increasing demands and the large variety of technical and economic requirements for future communication-and application satellites necessitate an advance of the efficiency in all areas of system development. In addition to technical performance improvements, optimal use of equipment, and ease of operability especially stringent economic boundary conditions are to be met. Such ambitious goals cannot be achieved on the basis of efforts made on the level of an individual subsystem and its equipment only but requires a well balanced overall system approach. Presently, based on a cooperation agreement between DASA/MBB and Aerospatiale companies, joint efforts are being undertaken towards an optimized approach of this kind, within the so-called “Spacebus Improvement Program” (SIP). The key issue of the approach adopted is an Integrated Control and Data System (ICDS), which combines the versatility and flexibility inherent to the Attitude-and Orbit Control Subsystem (AOCS) with the Data Management and Control (DMC) tasks, making best possible use of modem equipment technology and onboard processing capabilities.