Publisher Summary This chapter discusses the cooperative spacecraft formation flying. Formation flying of multiple spacecraft is an enabling technology for many future space science missions including enhanced stellar optical interferometers and virtual platforms for Earth observations. Controlling a formation will require several considerations beyond those of a single spacecraft. Key among these is the increased emphasis on fuel savings for a fleet of vehicles because the spacecraft must typically be kept in an accurate formation for periods on the order of hours or days, and the performance of the formation should degrade gracefully as one or more of the spacecraft runs out of fuel. This chapter presents a model predictive controller that is particularly well-suited to formation flying spacecraft because it explicitly minimizes fuel use, exploits the well-known orbital dynamics environment, and naturally incorporates constraints.