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Two teachers and a parent used three basic multiple baseline designs to investigate the effects of systematic reinforcement and punishment procedures in the classroom and at home. (1) A fifth‐grade teacher concurrently measured the same behavior (tardiness) in three stimulus situations (after morning, noon, and afternoon recesses). Posting the names of pupils on a chart titled “Today's Patriots” was made contingent on being on time after the noon recess, then successively also the morning and afternoon recesses. Tardiness was reduced to near zero rates at the points where contingencies were applied. (2) A highschool teacher recorded the same behavior (daily French‐quiz grades) of three students. She then successively applied the same consequences (staying after school for individual tutoring for D and F grades) for each student. At the points where the contingency was applied, D and F grades were eliminated. (3) A mother concurrently measured three different behaviors (clarinet practice, Campfire project work, reading) of her 10‐yr‐old daughter. She successively applied the same contingency (going to bed early) for less than 30 min spent engaged in one after another of the behaviors. Marked increases in the behaviors were observed at the points where the contingency was applied.

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Three pigeons obtained food on a one‐key schedule of reinforcement for two concurrent, discriminated interresponse times. The overall rate of reinforcement was determined by a family of variable‐interval schedules and by a continuous reinforcement schedule. The average frequency of reinforcement varied from 1.1 to 300 reinforcements per hour; the relative frequency of reinforcement for each of the two interresponse times was 0.5 throughout the experiment. The number of responses per minute increased sharply as the number of reinforcements per hour increased from 1 to 20. Beyond 30 reinforcements per hour, the curve was approximately flat, although it sometimes decreased slightly at the highest reinforcement rates. The relative frequency of the shorter interresponse time also increased sharply as the number of reinforcements per hour increased from 1 to 20. The asymptote of the relative frequency function approximately equalled the relative reciprocal of the length of the shorter interresponse time for reinforcement rates greater than 30 or 40 reinforcements per hour. This approximation was obscured by the response‐rate function.

Cumulative time measures of classroom attention, as delineated by the teacher, were taken of four elementary classes (kindergarten, third, fifth, and sixth grades) and of 16 randomly chosen students in these same classes. Each class of students was viewed as an individual responding organism. Base rates showed considerable variability. Explicit instructions alone concerning student attention produced temporary increase for some students and for some grades. Adding group contingencies (i.e., contingencies dependent on the attention of every student in the class) and token‐mediated reinforcement to class achievement of a gradually increasing attention criterion raised group measures to a consistent 70 to 85% level of time attending to task as instructed, and raised individual student measures to a stable 90 to 100% level. Reversals and other data indicate that the elementary teacher can, by herself and with little effort, maximize what she considers the “paying‐attention behavior” of all her students by her less‐than‐precise measure and consequation of the attention of the class as a whole.

Hyperthermia was observed at the end of each conditioning session in rats trained to avoid electric shocks by jumping on a platform. The temperature rise was also observed after the conditioned behavioral response was well established and was elicited even in the absence of shocks. There was no tendency for the hyperthermia to diminish over the course of nine extinction sessions.

Pigeons' key‐pecking responses were reinforced in the presence of a compound stimulus that consisted of an auditory feature (a tone) and a visual feature (a light) and non‐reinforced in the presence of a compound stimulus that was either a noise and a dark key, or noise and a light. In the condition where reinforcement trials differed from non‐reinforcement trials on the basis of both auditory and visual features, the tone exerted very little control over responding on test. In the condition where reinforcement differed from non‐reinforcement trials solely on the basis of the auditory features, an abrupt and a gradual introduction of the visual feature of the negative stimulus, a light, were compared for their effect upon control in the compounds. The tone acquired strong control in both cases. Evidence indicated that the tone had acquired control in the gradual condition without the occurrence of responses to the negative stimulus. An incidental finding was that when the negative stimulus consisted of a noise and a light, which was introduced abruptly, responding over the light dimension with tone, on test, was peaked at a point other than that light value used as positive and negative during training.

After 25 free‐operant avoidance training sessions, a 1‐min signal followed by a brief shock was presented on the average of once every 4 min. During the signal, the avoidance schedule was suspended (20 sessions). Response rates during the signal were markedly reduced. Shock rates during non‐signalled periods increased. Fifteen additional sessions were given during which the signal was presented without shock. Response rates during signalled periods were greater than previously observed during signalled periods, indicating that signalled shock had suppressive control over a previously acquired avoidance response rate.

In the first of two experiments, responses of two pigeons were maintained by multiple variable‐interval, variable‐ratio schedules of food reinforcement. Concurrent punishment was introduced, which consisted of a brief electric shock after each tenth response. The initial punishment intensities had no lasting effect upon responding. Then, as shock intensity increased, variable‐ratio response rates were suppressed more quickly than variable‐interval response rates. When shock intensity decreased, variable‐interval responding recovered more quickly, but the rates under both schedules eventually returned to their prepunishment levels. In the second experiment, the following conditions were studied in three additional pigeons: (1) With each shock intensity in effect for a number of sessions, punishment shock intensity was gradually increased and decreased and responding was maintained by multiple variable‐ratio, fixed‐ratio schedules of food reinforcement; (2) Changes in punishment shock intensity as described above with responding maintained by either a variable‐ratio or a fixed‐ratio schedule, which were presented on alternate days; (3) Session‐to‐session changes in shock intensity with responding maintained by multiple variable‐ratio, fixed‐ratio schedules. Responding under the two schedules was suppressed to approximately the same extent by a particular shock intensity. Also, post‐reinforcement pauses under the fixed‐ratio schedule increased as response suppression increased.

The effect of two shock intensities (1.00 and 2.00 mA) were studied in the acquisition, maintenance, and extinction of unsignalled avoidance by albino rats. Single and multiple avoidance schedules were employed, with shock intensity being the principal condition that differed between schedule components. The higher shock intensity was generally more effective in producing avoidance. Higher response rates and lower shock rates were observed under high‐intensity shock when performance stabilized. When the multiple schedule was introduced, the six rats trained under a single shock intensity all showed poorer performance under the new shock intensity, whether it was higher or lower than the training intensity. Performance under the original shock intensity did not change substantially with the introduction of a different shock intensity in the other multiple schedule component. Performance under the new shock intensity showed gradual improvement with continued exposure to it. All of the rats showed persistent “warm‐up”, receiving approximately 40% of the total session shocks in the first one‐sixth of the session. The degree of warm‐up was unrelated to avoidance shock intensity.