QMC2 is the successor of one of the first UNIX M.A.M.E. GUI front ends available on this planet called QMamecat (derived from MAMECAT, which was text-only). QMamecat was based upon Qt 2; its development was frozen in 2003. By the beginning of March 2006, we started to build QMC2 from scratch as a Qt 4 project. Parts of the design and code were inspired by its predecessor, but it's not just a remake. We tried to make the new design as flexible as possible to minimize dependencies from front end and CLI related MAME changes, which was a major deficiency of QMamecat. QMC2 now uses a template based emulator configuration scheme, which can easily be enhanced with additional command line options (defined in an XML template file). Status As a result of this flexible design and countless hours of work, QMC2 today is not only a stable, feature-rich and fast multi-platform GUI front-end for M.A.M.E. (Multiple Arcade Machine Emulator) but also a fully-featured ROM manager for this emulator (and its derivatives, older versions of MAME or even foreign emulators when they use the same/similar XML syntax) through the built-in ROMAlyzer. QMC2 is known to work on any modern Linux/UNIX distribution, on Mac OS X and Windows (XP, Vista, 7, 8, 8.1 and 10).