During the last few years there has been an increasing number of reports from the staff in low level acceptance institutions as well as from streetworkers, about poor physical condition among drug addicts and young drifters. In May 1993 this caused the Public Health department of Cologne to set up a mobile medical service. This service offers consultation hours in so called "contact cafes" as well as in an out-of-service ambulance for drug addicts of the open drug scene and young drifters around the central station. Past experience has shown that the affections are by no means trivial ones. Phlegmoneous inflammations, abscesses, parasitosis and pyodermias of any kind as well as lesions of peripheral nerves and different kinds of acute or chronic virus infections are among the diseases. Without medical treatment there will be grave consequences. Difficulties in the treatment of drug addicts and other marginal social groups formed the term of the patient "who resists any medical treatment". As a result of bad experiences with existing medical institutions drug addicts consult the doctor either too late or they break off the treatment too early. In the treatment of drug addicts and young homeless it is absolutely necessary to face them without any prejudice and to create an atmosphere of confidence in order to guarantee an efficient medical care. There traditional medical services are not able to provide medical aid, the public health department is obliged to establish possibilities of complementary treatment. Drug addiction and homelessness cannot mean exclusion from medical care. That would also mean that the health insurances should participate in the costs.