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Contingency contracting procedures used in managing problems with school‐age children involved analyzing teacher and/or parental reports of behavior problem situations, isolating the most probable contingencies then in effect, the range of reinforcers presently available, and the ways in which they were obtained. The authors prepared written contracts delineating remediative changes in reinforcement contingencies. These contracts specified ways in which the child could obtain existing individualized reinforcers contingent upon approximations to desired appropriate behaviors chosen as incompatible with the referral problem behaviors. Contract procedures were administered by the natural contingency managers, parents and/or teachers, who kept daily records of contracted behaviors and reinforcers. These records were sent to the authors and provided feedback on the progress of the case. Initial results of this procedure have been sufficiently encouraging to warrant recommending an experimental analysis of contingency contracting as a clinical method.

For the contingency management techniques first devised by Keller (1966, 1968) to become a widely accepted teaching method, it is necessary that they be shown (1) to be applicable to general subject matter and (2) to be superior to traditional lecture methods. The present study demonstrated (1) by successfully teaching the material from a standard psychology text. The superiority of contingency management was established by direct comparison of final examination scores from comparable groups taught the same subject matter by either Keller's method or traditional methods. Students taught by Keller's method also rated the course more favorably.

The control of toothbrushing behavior by contingency management was studied with eight, 10 to 12‐yr‐old boys at a summer camp for children. This behavior occurred infrequently during baseline conditions with and without verbal instructions to the subjects to brush their teeth. Toothbrushing behavior was maintained at a high level when the behavior was required as a prerequisite for the opportunity to swim (contingency management). When, after 22 days, the contingency arrangement between toothbrushing and swimming was terminated, toothbrushing behavior returned to a low level.

Three groups of albino rats were trained under a free‐operant avoidance (Sidman) procedure with equal shock‐shock and response‐shock intervals. After stable performance was achieved, the animals were concurrently exposed to a brief electric shock after each response. The procedures were as follows: Punishment Schedule I: punishment shock was introduced at an intensity approximately one quarter that of avoidance shock; increments of nearly this same size were made as stable performance was achieved at succeeding punishment shock intensities. Punishment Schedule II: punishment shock was introduced at approximately one‐half the intensity of avoidance shock; after stable performance, punishment shock was increased to the same intensity as avoidance shock. Punishment Schedule III: punishment shock was introduced and maintained at the same intensity as avoidance shock. Punishment was continued for all groups until one of two suppression criteria was attained. All animals made fewer responses and received more avoidance shocks as a function of increasing punishment shock. Half of the animals under Punishment Schedule I required punishment shock higher than avoidance shock to meet their assigned suppression criterion. A comparison of all procedures showed that suppression was greater when punishment shock was initially at high intensity.

Twenty four subjects were studied for ten 1‐hr sessions to determine whether the human observer's visual monitoring of individual meters in a complex display can be differentially controlled by concurrent scheduling of signals. Subjects were divided into two main groups of 12 each. One group was given fixed‐interval, variable‐interval, and differential‐reinforcement‐of‐low‐rates schedules. The second group was given fixed‐interval, fixed‐ratio, and differential‐reinforcement‐of‐low‐rates schedules. Test subjects were instructed only to detect as many signals as possible. Results indicated that observing responses to the individual meters corresponded to the temporal patterns known to be associated with the schedules for the group given fixed‐ratio instead of variable‐interval as a component schedule. The group given the variable‐interval schedule in the three‐schedule combination tended to exhibit the same pattern of viewing across each of the three meters during any given session. However, subsequent testing was performed on two more subjects over 64 sessions, by adding initial feedback of signal detection results, and instructions concerning schedule construction. These results indicated that with knowledge of schedule construction and initial feedback of detection data, differentiated responding can be maintained efficiently over long periods of time by the combination including fixed‐interval, variable‐interval, and differential‐reinforcement‐of‐low‐rates schedules.

In the first of two studies, the responding of four albino rats was differentially reinforced in the presence of noise and light together and then tested in the presence of the noise and the light separately during extinction. The light exercised substantially more control of responding than did the noise. In the second study the responding of a similar group of four rats was differentially reinforced in the presence of the noise and the light separately. Control of responding by the light developed more rapidly than control by the noise. Results suggest that levels of control by stimuli after differential reinforcement with respect to the stimuli together can be predicted by the rates of development of control during differential reinforcement with respect to the stimuli separately.

The control of responding by the location of tone bursts of 0.2‐ or 50‐msec rise time was investigated in three albino rats. The apparatus consisted of an enclosure with two levers, two loudspeakers (in different locations), and a dipper feeder. The animal was exposed to tone bursts from either one or the other of the two speakers, and the speaker through which the tone bursts were delivered on any particular trial alternated in an irregular manner. Responses on one lever were reinforced with food in the presence of tone bursts from one speaker; responses on the second lever were reinforced with food in the presence of tone bursts from the second speaker. Responding came under the control of the location of 4‐kHz tone bursts of 0.2‐msec rise time within the first session. At this rise time, animals maintained a stable level of correct responding of greater than 95%. When the rise time was increased to 50 msec the percentage of correct responding fell to an average of 80 to 85%. It was concluded that location of an auditory stimulus is a powerful controller of responding in rats and that the degree of control is dependent upon rise time.

Both high and relatively constant rates of responding without post‐reinforcement pauses and lower rates with pauses after reinforcement are produced by human subjects under fixed‐interval (FI) schedules. Such FI rates and patterns may be controlled when subjects are provided with different histories of conditioning and different conditions of response cost (reinforcement penalties per response). Subjects with a conditioning history under ratio schedules typically produce high and relatively constant rates of responding under FI schedules; this responding does not change systematically with changes in FI value. In contrast, subjects with a history under schedules which produce little or no responding between reforcements [such as differential‐reinforcement‐of‐low‐rate (DRL) schedules] tend to pause after reinforcement and respond at low rates under FI schedules, whether or not they also have ratio conditioning histories; cost increases the likelihood of this type of performance. For DRL‐history subjects, post‐reinforcement pauses increase and response rates decrease as FI values increase.

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