Mercedes-Benz has Brabus, Audi has ABT and BMW has Alpina. Unlike M Motorsports which manufactures performance cars that are more track-focused, Alpina distincts its products with simplicity and everyday usability.
As the German tuner works closely with BMW and their processes are integrated into BMW's production lines, Alpina is perhaps one of the few aftermarket tuners that is recognised as an automobile manufacturer by TUV. The short video gives you a peek behind the makings of an Alpina.