• experimental design;
  • extinction;
  • differential reinforcement of alternative behavior;
  • differential reinforcement of other behavior;
  • contingency reversal;
  • noncontingent reinforcement;
  • reinforcement control procedures;
  • reversal designs

A demonstration of the effects of reinforcement requires comparison of response rates in the presence of a contingency with those in another condition that controls for the influence of extraneous variables. We describe several control conditions that have been used in evaluating the effects of positive and negative reinforcement. The methodological rigor and practical utility of each type of control condition are discussed, and recommendations for the use of these conditions are presented.