The digest presents the background and reasons for early intervention with children at risk for handicaps. Early intervention is defined, and three primary reasons for intervention are cited: (1) to enhance the child's development, (2) to provide support and assistance to the family, and (3) to maximize the child's and family's benefit to society. Research on the effectiveness of intervention is briefly reviewed, and it is stated that despite research problems, qualitative and quantitative data show that early intervention increases the developmental/educational gains for the child, improves the family's functioning, and provides long-term benefits to society. Long-term cost savings are noted from three research studies. Three factors important in effective intervention are noted: intervention as early as possible; involvement of parents; and programs featuring a high degree of structure, intense services, and an individualized approach. A list of references and resources concludes the digest. (CL)