Health care that is provided through a network of hospitals and doctors is a health maintenance organization (HMO). The benefits usually include preventative care, such as physical examinations, weight control and stop-smoking programs, baby care and immunizations. The most common characteristic of HMOs is that the primary care provider is limited to only one doctor within a network, although there is usually a variety to choose from. Outside of the network of hospitals and doctors of the HMO, there is no coverage. Due to the limited choices, the costs are lower. The payment for the HMO premiums are fixed and per employee. A small co-pay is due for the medical services, and no reimbursement is necessary.