This is a step-by-step guide to developing a social skills curriculum and designing its instruction. It teaches how to construct assessments and plan interventions to address problems in student social behavior using procedures that can be used to set instructional goals and develop interventions for almost any student who has trouble with social interaction. Using a continuing case study that focuses on three fifth-grade students who have social problems, the guide illustrates each of the steps for assessing behavior and planning interventions. Part 1 discusses competent social behavior and the importance of social skills. Part 2 explains how to assess a student who lacks social competence. How to develop and implement interventions is the focus of part 3, and part 4 examines ways to modify and extend the process of assessment and intervention in actual practice. Worksheets in every chapter can be used to help implement the developed procedures. Appendix A contains a checklist of expectations for social behavior from preschool through high school. Appendix B is a list of 33 resources and teaching materials. (Contains 26 figures, 30 tables, and 138 references.) (SLD)