The increasing presence of industrial control systems in high-energy physics laboratories raises the questions of their integration into the general control infrastructure and the organisation of the operation of the associated equipment. The method of integration is dictated by the adopted operation strategy; in turn, the latter determines the former. After an introduction to industrial control systems this paper describes different communication mechanisms with alien systems provided by

more »

... s provided by manufacturers and reports on experience acquired at CERN. The major operation strategies in terms of level of coupling are described and their requirements on the integration methods are discussed.