Who takes Combined Medical services (CMS) examination?

CMS is conducted mainly to recruit medical officers in various government organizations. The requirement changes every year and detailed notification is published in newspapers.
Services/posts offered
1) Assistant Divisional Medical Officers in Railways
2) Assistant Medical Officer in Indian Ordnance factories Health service
3) Junior Scale Posts in Central health Services
4) Medical Officer’s in the Municipal Corporations
5) General deputy Medical Officer in Municipal Council

list of Colleges under Combined Medical Services