Primary health-care providers have been encouraged to counsel their patients about regular physical activity, but there are significant barriers to effective counseling. In this study a program of training and materials was tested for acceptability to providers, office staff, and patients. Primary care providers and office staff were trained to use the Physician-based Assessment and Counseling for Exercise (PACE) materials in four geographical sites in the United States. The program was tested in a variety of settings and with diverse patient populations. The acceptability of the program during a five-month study period was evaluated through structured interviews. The training was effective in preparing the providers to counsel, and the program was generally acceptable to providers, office staff, and patients. Counseling was provided in less than five minutes by 70% of providers, and most patients reported following the recommendations given. The PACE program assists providers in overcoming barriers to counseling patients about physical activity. The PACE program is potentially an important part of a national effort to enhance the adoption and maintenance of physical activity among adults.