The final report details the background and activities of the Institute for the Study of Exceptional Children, an interdisciplinary collaborative effort of two research-service organizations: the Infant Laboratory of Educational Testing Service in Princeton, New Jersey, and the Pediatrics Service of the Roosevelt Hospital in New York. An introductory section reviews the Institute's theoretical principles as well as its structure, goals, functions, and priorities. Four goals are identified: identification of young children at risk for handicaps; assessment of their social, emotional, and cognitive functioning; intervention; and training of professionals in an interdisciplinary setting. Activities from each of the Institute's 5 years are summarized. The administrative organization, with its four units (detection, research, intervention/evaluation, and training/products/dissemination units) is described. The largest part of the final report is devoted to indepth information on activities of each of the four units. Among detection unit projects discussed are a project to identify handicaps in a population of at-risk infants and a project to develop instruments for measuring infants' competencies. Among projects of the research unit are studies of contingency learning in 10-week-old and premature infants and of infant attention. Three major activities of the intervention and evaluation unit (contingency intervention, communication development, and evaluation) are considered. Three final chapters detail the Institute's products (publications, presentations, and technology and assessment instruments), dissemination efforts, and training activities. (CL)