The Individualized Critical Skills Model (ICSM) is an individualized, systematic instructional process that emphasizes teaching severely handicapped learners relevant skills in the environment in which they would naturally occur. The manual is divided into three sections. The first section discusses the historical perspective of the ICSM and gives the rationale and purpose for its development. The second section provides details of the ICSM instructional process. Each of the 10 phases of the ICSM is then covered in one or more chapters. The final section deals with integrating and applying the ICSM approach. The appendix contains blank copies of 29 worksheets used in conjunction with the ICSM, and a glossary of terms. Individual chapters focus on the following topics: conducting interviews with "significant others," targeting critical activities, determining the student's present level of performance, developing adaptations for participation in critical activities, developing annual and instructional objectives, teacher additions to the instructional process, instructional procedures, keeping records, scheduling and implementing programs, evaluating and modifying programs, evaluating student progress, and putting it all together. (DB)