1. Advances in these technologies will provide reductions in weight, power, and volume, and improved reliability in small spacecraft computers at ever-reduced costs. Today a 2000- word, 30-jusec-add-time, 15-lb, 15-w, simple general purpose (GP) computer can be built. With enough care in manufacture and testing, 2- to 3-yr mean times between failure (MTBF's) are realizable. In 4 to 5 yr, a 5-lb, 3-w,GP computer with a capacity of 4000 words and 10-jusec add time with an MTBF of 4 to 5 yr will be commonplace. However, MTBF's of 15 to 30 yr will be required for some future longterm space missions. Reliabilities of this order probably will be obtained through the use of various redundancy techniques now being investigated and by more extensive use of magnetics.