The story
German Doctors e.V. was founded in 1983 as „Ärzte für die dritte Welt“ in Frankfurt am Main, Germany. The idea was to create a charity organisation with German doctors, who work without remuneration in the third world countries. The doctors use their annual vacation to work for the project.
From Wikipedia’s article on German Doctors for Developing Countries, shared under CC BY-SA 4.0.5