The Master of Surgery (Latin: Magister Chirurgiae) is an advanced qualification in surgery. Depending upon the degree, it may be abbreviated ChM, MCh, MChir or MS. At a typical medical school the program lasts between two and three years. The possession of a medical degree is a prerequisite. The ChM can be awarded on both clinical and academic competency or on academic competency. The regulations may ask for surgical experience and a thesis topic that is not purely medical.