We attempted to isolate the evocative effects of the establishing operation for positively reinforced problem behavior with 2 participants. The study consisted of three phases. First, a functional analysis identified tangible items (Participant 1) and attention (Participant 2) as maintaining problem behavior. Second, access to tangible items and attention was systematically controlled (continuous access vs. no access) immediately prior to functional analysis sessions in which these consequences were delivered contingent on problem behavior. Results of this phase indicated that problem behavior occurred at higher levels when access to tangible items and attention was restricted. In the third phase, prior access was again controlled, but problem behavior produced no consequences. Results of this final phase indicated that problem behavior occurred at higher levels during extinction sessions when participants did not have prior access to the reinforcers. (Contains 1 figure.)