Master of Medicine (MMed) is a postgraduate professional clinical degree awarded by medical schools to physicians following a period of instruction, supervised clinical rotations, and examination. The degree usually takes three years to complete, but may take up to four years in some countries. It is awarded by both surgical and medical subspecialties and usually includes a dissertation component. The degree may complement an existing fellowship in the chosen specialty or be the sole qualification necessary for registration as a specialist. The advantages of an MMed over membership certificated qualifications are that, whilst both groups are clinically competent at their levels, an MMed specialist can enroll into a four-year PhD plus fellowship and complete as consultants with a PhD, or do a two-year fellowship without a PhD. However, members of various professional colleges only advance to fellowship graduating as non-PhD consultants which reduces their academic ranking, as most universities insist on a PhD for their teaching staff. Another advantage of an MMed is that it takes less years to sub-specialise compared to professional membership which often hold practitioners as 'general specialists' even at fellowship level. It is envisaged that, most professional colleges will soon adopt the MMed and Fellowship/PhD certification system. As of May 2009, the following universities in the following countries award MMed degrees leading to specialists practice in the following subjects: Australia University of Queensland MMed in General Practice MMed in Primary Care Skin Cancer Medicine University of Sydney MMed in Ophthalmology MMed in Sleep Medicine MMed in Critical Care Medicine Monash University MMed in Perioperative Medicine P.R. China Chinese Universities in collaboration with their affiliated hospitals award two categories of master's degrees of Medicine: Specialty MMed or Academic MMed degrees. Specialty MMed degrees are awarded after a supervised rotational training in the university's Affiliated Teaching hospitals and lead to registration as specialist. Academic MMed degrees on the other hand are Research and Basic Sciences oriented, focusing more on medical laboratory research . Both qualifications are acceptable prerequisites for PhD enrolment. The entry requirements of both Specialty and Academic MMed programs are MBBS or related undergraduate medical qualifications. Graduates of Specialty MMed qualifications can either choose to practise as specialist physicians and surgeons in their respective specialties or undergo subspecialty PhD/Fellowship training leading to an advanced specialisation practice as consultants. The most important condition for gaining admission into MMed program is the availability of supervising professors or consultants