A series of instructional manuals in behavior modification with retarded children was tested as a self-contained resource and as part of three larger training programs involving different amounts of professional assistance to parents: telephone consultations, training groups, training groups plus home visits. One hundred and sixty families were randomly assigned to the four training conditions or to a delayed-treatment control group. The 20-week treatment period emphasized the programming of self-help skills, but also provided an introduction to programming language skills and managing behavior problems. The manuals-alone format was as effective as the more expensive training formats in producing gains in children's self-help skills and fostering knowledge of behavioral principles in mothers. The two group-training formats produced more efforts at behavior-problem management, greater gains in knowledge of principles by fathers, and higher self-confidence as teachers. Telephone consultation was generally the least effective training format; the manuals-alone condition was surprisingly effective. Some implications of the results for future strategies of family intervention were discussed.