Digital computers have become indispensible aids for many laboratory disciplines, allowing the performance of experiments which would be infeasible without the aid of a computer. Until recently, these computations have usually been carried out off-line, i.e., experimental data has been acquired in real time and subsequently processed on a large central computer. Small, relatively inexpensive digital computers first entered the laboratory as a substantial aid in real-time acquisition of data and control of experiments. Such computers, however, suffer severe limitations with regard to ultimate processing of the data. Hence the data processing must still generally be done on a large computer. To realize the full potential of computer-instrument interaction, one should use the computer to: acquire data while performing requisite control of an experiment; calibrate, reduce, and compare the data with files of known physical parameteorsr theoretical calculations; and finally, produce desired reports and documentations of the experiment. In order to obtain results soon enough to effect the next experiment, i.e., in minutes, or at most, tens of minutes, all of the foregoing steps should preferably be carried out in single computer. Fulfilling all of these needs requires a computer too large and expensive to be dedicated to most single experiments. Therefore, a computer shared among several instruments is required. A computer system which simulates the independence of small dedicated computers, but which is also capable of performing medium- to large-scale computations when they are required, is most desirable. Of course, many of these statements are controversial, and in order to investigate the validity of this approach an experimental computer system has been designed and implemented specifically for automation of multiple laboratory instruments in a timeshared mode. Experience gained from the simultaneous operation of a mass spectrometer, a nuclear magnetic resonance spectrometer, and two gas chromatographs is presented. The application programs and some proposed augmentation of these programs are also discussed.