This book presents results of a three-year study of children's living and play areas in three cities (one large, one medium, and one small) in Yugoslavia. A total of 1,200 families living in 240 buildings in six developments built between 1961 and 1971 were included in the study. A variety of facilities were evaluated for both formal and informal play areas, including consideration of: (1) the plan of the site, design of buildings, and use of apartment space; (2) the arrangement of neighborhood day care centers; and (3) the location, inventory, and adequacy of nearby schools, playgrounds, and/or play field facilities for serving children 3-14 years of age. The multidisciplinary research program focused on the functionally and safety of these informal living and formal play areas, their suitability for the intended age group, their influence on behavior and on physical and psychological health and development and the parents' and children's problems and satisfactions. Questionnaires, inventories, and on-site observations provided the data. Recommendations are included, as well as descriptions of the research instruments used. (ED)