HMO = Health Maintenance Organisation:
HMO is a health insurance model. The policyholder is required to consult a certain physician practising in a HMO centre, if he falls ill. This doctor is called a "gatekeeper". Emergencies, the annual gynaecological check-up as well as check-ups at the eye doctor are exceptions to this rule.
The HMO doctor is paid a flat monthly rate for all treatment his registered patients might need. This flat rate covers all costs for treatment provided either by himself, by specialists or during a hospital stay.
The gatekeeper principle enables the HMO doctor to coordinate his patients' treatment. The flat rate forces him to restrict treatment to what his patient needs. HMO premiums are up to 25% lower than standard basic health insurance rates for the same extent of benefits.
In case of emergencies:
HMO policyholders must always consult their HMO doctor first. Should he/she not be available or if the policyholder is away from their place of residence or work, they must seek out the nearest available emergency physician. After the emergency treatment, the HMO policyholder must contact the HMO physician to discuss further procedures.
You will find a list of HMO practices here.