The fourth of five volumes on the means by which Canadian communities can reduce the incidence of mental retardation, minimize existing impairment, and improve the quality of life of the mentally retarded, this booklet focuses on the prevention of mental handicap in adults and ways to accommodate and encourage community participation by the handicapped. The approach is based on a four-level prevention model which distinguishes between impairment, disability, handicap, and the feedback role of the environment. After an introduction, there are sections which deal with the following topics and examples: rights, freedoms, and responsibilities (equal opportunity and quality services); helping individuals with severe disabilities participate in community life; technological advances (communication and mobility aids); community homes; common features of successful community living arrangements; adult education for everyone (including the retarded); employment options (job sharing, jobs which often have a high turnover rate); living together, marriage, and parenthood; and getting older. (DB)