A NATO Advanced Study Institute (ASI) on the Behavior of Systems in the Space Environment was held at the Atholl Palace Hotel, Pitlochry, Perthshire, Scotland, from July 7 through July 19, 1991. This publication is the Proceedings of the Institute. The NATO Advanced Study Institute Program of the NATO Science Committee is a unique and valuable forum, under whose auspices almost one thousand international tutorial meetings have been held since the inception of the program in 1959. The ASI is intended to be primarily a high-level teaching activity at which a carefully defined subject is...