This chapter examines the effects of diagnosis related groups (DRGs) on the professional independence of physicians in three distinct types of healthcare systems: the U.S. private insurance system, where DRGs were first developed and subsequently implemented in the public Medicare program in 1983; the British National Health Service (NHS), which adopted an analogous version of DRGs referred to as Health Resource Groups (HRGs) in 1992; and the German social insurance system, which adopted its own DRG version (G-DRGs) based on a refined version of the Australian model that is to be fully phased into the hospital system by 2009. By examining these three cases, the present contribution asks (a) whether it is possible to identify any effects of DRGs on the professional independence of physicians; and (b) whether these effects are specific to the respective healthcare system and/or DRG version at hand.