Rochester's Intelligent Gateway (RIG) system provides convenient access to a wide range of computing facilities. The system includes five large minicomputers in a very fast internal network, disk and tape storage, a printer/plotter and a number of display terminals. These are connected to larger campus machines (IBM 360/65 and DEC KL10) and to the ARPANET. The operating system and other software support for such a system present some interesting design problems. This paper contains a high-level technical discussion of the software designs, many of which will be treated in more detail in subsequent reports.