Differential reinforcement of other behavior (DRO) and noncontingent reinforcement were compared as control procedures during the modification of a 3-yr-old preschooler's compliance. The recorded reinforcer was teacher proximity (within 3 ft (0.9 m) of the subject for at least 5 sec) which was often accompanied by positive verbal comments that varied in content across experimental conditions. The verbal content during contingent reinforcement might have been: "Thank you for picking up the blocks"; during noncontingent reinforcement: "You're wearing a pretty dress"; and during DRO: "I don't blame you for not picking up because it isn't any fun". Contingent reinforcement increased compliance in all manipulation conditions. Noncontingent reinforcement decreased compliance during two reversal conditions. However, the behavior was variable and did not decrease to the low levels reached during the two DRO reversals.DESCRIPTORS: compliance, DRO, noncontingent reinforcement, operant, reversals, teacher behaviorIn addition to extinction, both noncontingent reinforcement and differential reinforcement of other behavior (DRO) have been used as control procedures for evaluating reinforcementbased behavior-modification techniques. For example, Azrin, Rubin, O'Brien, Ayllon, and Roll (1968), Buell, Stoddard, Harris, and Baer (1968), Miller and Miller (1970, Phillips (1968), Siegel, Lenske, andBroen (1969) of special-education students, implemented DRO to decrease further the behavior in the reversal.These applied studies did not compare the two procedures in terms of how rapidly the response decreased or how durable was its elimination. Although Peterson et al. (1971) used both noncontingent reinforcement and DRO for a reversal, they did not directly compare the two as control procedures. Instead, after a baseline and a treatment condition, they first used noncontingent reinforcement for a reversal and then immediately reduced the target behavior even further by implementing DRO. That sequence of two conditions prevents their direct comparison for efficiency, rapidity, or durability of response elimination. DRO may have seemed more effective in these ways because of its interaction with the weakening already produced by the preceding noncontingent reinforcement. That is, DRO was applied to a lower rate of behavior than was noncontingent reinforcement.In two animal studies, response elimination during DRO was compared with that during extinction. Uhl and Garcia (1969) (SPRING 1975)