In light of debate about the developmentally inappropriate and culturally questionable use of standardized testing for placement of preschool children, alternative approaches to screening and assessment are required. The impact of a Head Start program upon children must involve documentation of physical and mental health, speech, hearing, vision, and overall wellness, as well as traditional developmental domains. In 1988, the Preschool Services Department of the San Bernardino County (California) Head Start Program reviewed a variety of developmental screening instruments, but decided to refine and use its own instrument, the Child Development Screening Form. The developmental status of 5,000 Head Start children was sampled during 2 consecutive program years using 60 observable behaviors representing standard developmental milestones. Teachers and aides attended inservice training for using the screening form. Screening was done both pre-program and post-program. For one of the sample years, the 2,753 children showed demonstrable developmental gains, an average of about 6 points across all domains out of a possible 20. Children with disabilities averaged an 11 point gain. The current version of the screening form has a developmentally appropriate set of items and differentiates development trajectories and variations. It is user- and child-friendly, economical, and meets Head Start requirements. (The screening form, charts of screening results, and 25 references are included.) (TM)