Contingency Management approaches involve administering a non-drug reinforcer after demonstration of abstinence from drug or alcohol use. CM approaches are grounded in operant learning theory. These procedures may use either stable or escalating reinforcement schedules. The reinforcer value adjusts according to duration of abstinence. The punchbowl method is an example of reinforcers, in which negative screens for drug use are rewarded with the opportunity to draw from a “punchbowl.”