The report summarizes an evaluation of the effects of summer programs on the behaviors and skills of 186 severely handicapped children. Programs were categorized by their orientation and by their length, resulting in five groupings: (1) 6-week high structure (educational skill and behavior goal-oriented), (2) medium structure (mixed recreational and educational), and (3) low structure (recreational) programs, as well as (4) short programs (2-4 weeks duration), and (5) no program groups. Analysis of scores on the Inappropriate Behaviors Observation Checklist (developed for the study) and teacher ratings of basic skills revealed evidence of retention and improvement in Ss from the more highly structured programs which emphasized skills and behaviors, when these were measured immediately following programs. Positive effects were maintained midyear for skills but not for behaviors. For recreational programs which did not focus on skills and behaviors, there was regression in behaviors immediately following summer programs, but the losses were reversed at midpoint in the subsequent school year. Although more Ss from all programs retained than lost skills, those from the more highly structured programs gained skills more frequently than any others, and they retained this favorable position during the subsequent school year. (Author/CL)