In this article, we present the results of our study on the design, construction and use of a multiple column exploratory gas chromatograph. This device has a single oven and a single hydrogen flame detector, but has five valves, injection ports and columns in parallel, so that any one of the columns may be connected to the detector by switching its valve. Our purpose in developing this device was to provide a compact and inexpensive arrangement whereby a number of packings could be held immediately available in standby condition for a quick qualitative evaluation in the separation at hand. The design has also proved useful for preparative chromatography on a small scale.