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Behavioral contrast can be defined as an inverse relationship between the conditions of reinforcement in one setting and the rate of responding in another setting. Behavioral contrast is a phenomenon that is reliably demonstrated in pigeons and rats and in the context of multiple experimental preparations with these animals. However, little research has been conducted on behavioral contrast in humans. Further, the role of verbal behavior in research on behavioral contrast in humans has not been investigated. This study examined behavioral contrast in college students in a series of 3 experiments. In Experiment 1, subjects were not given accurate descriptions of experimental contingencies, and behavioral contrast was not reliably observed. In Experiment 2, specific, accurate descriptions of contingencies were provided to subjects at all times, and contrast was observed for 4 of 10 subjects. In Experiment 3, descriptions of experimental conditions were provided only during extinction, and behavioral contrast was observed for 4 of 5 subjects. The results suggest that accurate rules describing experimental contingencies may enhance or decrease the probability that contrast will be observed in human operant experiments, depending on which contingencies, if any, are accurately described.