The use of the ISR for experiments

The layout of the ISR is discussed showing the situation of the six intersections presently used for physics experimentation. A brief discussion of some of the physics equipment installed is included. A description of an intersection region is given showing the space available and the constraints imposed by the vacuum chamber. The use of the machine for physics is discussed, the measurement of the luminosity at all the intersections, minimisation of background etc., the ISR control computer playing a large part in these operations. A section describing the so-called Split Field Magnet facility is included. (1 refs).