By promoting the right “dosage” of physical activity, health care providers are prescribing a highly effective “drug” to for the prevention, treatment, and management of more than 40 of the most common chronic health conditions. The guide acknowledges and respects that healthcare provider may have only a brief window of time for physical activity counseling during a normal office visit. Given this time period, the guide intends to empower primary health care providers to 1) Assess the physical activity level of patients; 2. Write a prescription for physical activity, depending on the health, fitness level, and preferences of patients, and 3. Refer patients to certified exercise professionals, who specialize in physical activity counseling.