Health maintenance organizations (HMOs) are a type of health insurance plan that usually limits coverage to care from doctors who work for or contract with the HMO. It generally won't cover out-of-network care except in an emergency. An HMO may require you to live or work in its service area to be eligible for coverage. HMOs often provide integrated care and focus on prevention and wellness. In addition to the monthly premium (which may be shared by the employer and employee), participants usually need to pay a small fee at the time of service called a copay (often in the range of $10 to $40), while the HMO covers 100% of the services provided.