This report documents the planning and development of Families First, an early intervention program to be implemented in Marin City, California. The program has been designed to integrate and coordinate the provision of a wide range of services to families of children from the third trimester of pregnancy to the age of 8 years who live in a low-income, mostly African-American community. The program is intended to enhance the children's intellectual, social, emotional, and physical development. Facilitation activities conducted by Far West Laboratory as part of its Bay Area Early Intervention Program in Marin City and the Western Addition of San Francisco led to the development of Families First. Discussion in this report on the program concerns theoretical and research foundations of the program, its intervention philosophy, its programmatic approach, and its goals, which concern children, program families, community functioning, and agencies. Documentation and evaluation of program efforts are seen as an integral part of the intervention. A list of participating agencies and their roles is provided. Appendixes include a bibliography of nine references and background information on Marin City. (GLR)