Day programs represent an increasingly important component in treatment for the elderly. Several attempts have been made to categorize the wide variety of such programs but little attempt has been made to analyze the dynamic rather than static nature of such program design. Dalton's model of induced change is tested and illustrated through application to a psychogeriatric day program. Some of the reasons for the evolution which took place in the program included realization of the incrcased need to serve long-term chronic psychiatric clients, staffing changes, heterogeneity of clientele, change in availability of alternate resources in the community. The advantages of program flexibility in a developing area such as day care are discussed.