A combination of aerobic activity, strength training, and flexibility exercises, plus increased general daily activity can reduce medication dependence and health care costs while maintaining functional independence and improving quality of life in older adults. However, patients often do not benefit fully from exercise prescriptions because they receive vague or inappropriate instructions. Effective exercise prescriptions include recommendations on frequency, intensity, type, time, and progression of exercise that follow disease-specific guidelines. Changes in physical activity require multiple motivational strategies including exercise instruction as well as goal-setting, self-monitoring, and problem-solving education. Helping patients identify emotionally rewarding and physically appropriate activities, contingencies, and social support will increase exercise continuation rates and facilitate desirable health outcomes. Through patient contact and community advocacy, physicians can promote lifestyle patterns that are essential for healthy aging.