More than 40 million Americans do not have a particular doctor's office, clinic, health center, or other place where they usually go to seek health care or health-related advice. Even among privately insured persons, a significant number lacked a usual source of care or reported difficulty in accessing needed care due to financial constraints or insurance problems. 

Clinical preventive services have a substantial impact on many of the leading causes of disease and death. People must have access to clinical preventive services that are effective in preventing disease (primary prevention) or in detecting asymptomatic disease or risk factors at early, treatable stages (secondary prevention).

Improving access to appropriate preventive care requires addressing many barriers, including those that involve the patient, provider, and system of care. Patient barriers include lack of knowledge, skepticism about the effectiveness of prevention, lack of a usual source of primary care, and lack of money to pay for preventive care. Although patient awareness and acceptance of some interventions are high (such as screening for breast cancer) other interventions (for example, colorectal cancer screening) are less uniformly accepted. A small but significant number of patients remain skeptical of even widely accepted preventive measures, such as immunizations. Having health insurance, a high income, and a primary care provider are strong predictors that a person will receive appropriate preventive care. Although reimbursement for common screening tests, such as mammograms and Pap tests, is provided by most health insurance plans (and is required by law in some States), reimbursement for effective counseling interventions, such as smoking cessation, is less common.

Increasing recognition of the critical role of preventive services across the continuum of care and the need for providers to incorporate preventive services into patient visits has led to the development of tools and projects designed to help providers and patients shift to a prevention-oriented health care system.