Early childhood programs are growing increasingly concerned about the number of preschoolers exhibiting challenging behavior. This case study describes how educators at the Visiting Nurses Association Child Care and Family Resource Center program addressed this concern by implementing the systems, data, and practices of Program-Wide Positive Behavior Support (PWPBS) as part of the statewide initiative called Positive Behavioral Interventions and Supports-New Hampshire. Features of PWPBS and examples from the "Be a Star at the VNA" program are described within the context of training and technical assistance. Descriptive data indicate that the program was implemented with fidelity and associated with increases in leadership, team functioning, and consistency in data collection. These results were associated with increases in the percentage of children who responded to primary prevention and decreases in the frequency of challenging behavior. Limitations are discussed. (Contains 2 figures and 3 tables.)