A social system and ecological, as well as individual, perspective is applied to the development of a psychosocial community-oriented data system for children's mental health services. A rationale for the evaluation procedure and the necessary criteria met by the data system are presented. The problem appraisal focuses on the assessment of multiple determinants of the child's behavior incorporating individual, family, organizational and ecological factors. The data system provides retrievable information on selected intake, intervention and outcome parameters. Applications of the data system to the intake assessment process, for administrative monitoring and review purposes, and as a training and research instrument are discussed. (Author)