Steady state multiplicity in exothermic adiabatic reaction systems oreviouslv been demonstrated bv a number of authors. SDecificallv. has the hork of Root and Schmitz provid the existence of multipll steady'states in a loop reactor, but difficulty was encountered in controlling such a reaction system at the intermediate steady states.Since a close analogy can be demonstrated between loop reactors and controlled cycled reactors (CCTR), it appeared reasonable to attempt to achieve steady state multiplicity in a CCTR. When the chemical reaction of Root and Schmitz was carried out in a CCTR, it proved relatively easy to obtain experimental values of intermediate steady states and to control the reactor at these conditions by means of a simple on-off temperature controller.This work suggests that chemical systems displaying steady state multiplicity can be experimentally investigated in a CCTR and that cyclic operation may be the best way for controlling such reactions systems.