Developmental Evaluation Services for Children (DESC) provides in-depth medical and educational diagnostic services for children in Montgomery County, Maryland, who are under 6 years of age and who are suspected of having handicapping conditions in two or more areas of development. This follow-up study was designed to determine the progress of students referred to DESC since 1976. Three types of data were collected: present placement and related special services received in 1982-83 by all Ss referred between 1976-1982; year-to-year placement histories on a sample of approximately half the Ss referred during 1977-78 and 1978-79; and in-depth case studies for a small sample of Ss (N=13). Findings addressed three major issues related to the clinic; appropriateness of the policy for acceptance for evaluation, most of the Ss evaluated by the clinic were found to be handicapped and to require special education for the next several years); stability of the diagnosis (evaluations were found to be comprehensive and accurate in identifying handicapping conditions and/or deficits in preschool Ss); and the effectiveness of early identification and intervention (almost 70% of the evaluated children were still in self-contained special education classrooms 5-6 years later). The existence of multiple impairments in many referred children affects the findings on intervention effectiveness. (CL)