Part of a volume which explores current issues in service delivery to infants and toddlers with handicapping conditions, this chapter discusses the nature of parent involvement in early childhood special education. Acceptance of the basic axiom of parent involvement needs to be accompanied by an understanding of individual differences in family styles and flexibility in the design of intervention methods. Strategies for involving parents in the process of parent-mediated instruction should also be individualized, and the needs of all family members taken into consideration. Four models of family functioning are described (family systems theory, ABCX, family life cycle, and transactional); common variables such as resources and parental expectancies are identified; and the impact of selected variables on the level and quality of family involvement is described. The Individualized Family Service Plan (IFSP) as an extension of the concept of the individualized education program is also discussed. Assessment of the child, the family, and the dynamics of parent-child interaction are described as providing important information for the IFSP planning conference. A sample family goal worksheet is presented, and a list of references concludes the chapter. (JW)