This volume, the first in a series of seven reporting the design, methodology and findings of the 4-year National Day Care Home Study (NDCHS), the first national study of family day care, provides a synopsis of the study's findings. Volume One consists of 10 chapters. Chapter I provides background information and an overview of the NDCHS. Design and methodology of the study are described in Chapter II. Chapter III summarizes findings concerning state regulation of family day care in San Antonio, Philadelphia and Los Angeles. The characteristics of family day care providers are reported in Chapter IV, and findings on the group composition of children in day care are reported in Chapter V. Characteristics of the parents of children in care are described in Chapter VI, and Chapter VII reports findings resulting from in-home observation of child/caregiver interactions. The costs of family day care to parents, government and caregivers are reported in Chapter VIII. Chapter IX describes the 22 family day care systems studied during the NDCHS. Conclusions and recommendations are offered in the final chapter. (Author/RH)