In this large scale study, the extent of parent involvement in preschool day care and its impact on staff and on classroom environments in child-centered and adult-centered situations were assessed. Subjects were 15 directors, 30 teachers, 524 children in 30 classrooms. Interview schedules and a classroom observation scale were the two instruments used. The findings indicate that: (1) the percentage of parents who are board members is not a determinant of parent influence; (2) there is a relationship between the amount of parent involvement in administrative areas such as fiscal control, hiring and firing, and personnel practices, and the amount of influence in curriculum/teaching areas; (3) this influence is mediated primarily through the director; (4) the amount of parent involvement is related to whether classrooms will be child-centered or adult-centered; and (5) this relationship varies with the social class status and educational level of parent policymakers. (Author/ED)