This monograph reviews and analyzes a set of treatment procedures exemplifying a positive or nonaversive approach to the amelioration of severe behavior problems in persons with developmental disabilities. Target behaviors include self-injury, aggression, and tantrums. Approximately 100 research articles drawn from 21 journals and a number of books and literature surveys are included. Specific interventions discussed include differential reinforcement of other behavior (DRO), differential reinforcement of incompatible behavior (DRI), skills acquisition, and stimulus-based treatments. Assessment and evaluation issues are discussed with respect to initial treatment effects and also in relation to stimulus generalization, response generalization, and maintenance. Variables found to be peripheral included gender, diagnosis, age, degree of retardation, and treatment setting. Variables that appeared to be central included extrinsic and intrinsic positive and negative reinforcers, and antecedent factors. Skills acquisition and stimulus-based interventions were found to be superior overall to DRO and DRI. (Over 200 references) (JDD)