The requirements for time-sharing a computer to control and monitor multiple experiments in a solid state physics and physical chemistry laboratory are discussed. A monitor system, which has been implemented on the IBM 1800, to control multiple spectroscopic experiments and collect their data is described. It provides flexible analog and digital input/output routines which, using a multilevel interrupt system, operate in a background mode once they have been initiated from a foreground program, and a priority queuing system to sequence these foreground programs. In addition, provision is made for the utilization of the computer on problems not associated with any connected experiment. A simplified sample application is presented. © 1968.