Presented is a sourcebook for the developmental play program, a relationship-focused, activity-based intervention program for learning problem, behavior problem, Headstart, and normal children (2- to 6-years-old) and a training model in child development and parenting for participating adults. Following an introductory section are descriptions of the program's goals and rationale (including the stimulation of child-adult attachment behavior); structure and program participants; goals and stages of one-to-one child-adult play; suggested one-to-one activities to encourage and establish physical contact, to encourage fantasy, to establish relationships with other one-to-one partners, and to help the adult respond to the child's cues; goals, stages, and activities for circle-time play; goals, stages, and activities for juice-time; songs for developmental play; selection, training, and development of program adults; and assessment methods and behavioral changes associated with developmental play. A final section covers such areas as selection of schools, equipment and space requirements, selection of adults and children, communication with parents, and some potential problems. Appendixes include statistical data showing the effectiveness of developmental play programs, suggestions for feedback for continuing research, samples of forms and rating scales used, quotes from participating adults, and sample handouts. (SBH)