AMG started off by designing and testing racing engines. They expanded their business into building bespoke road cars, based upon standard Mercedes cars.

By the early 1980s, AMG had moved to nearby located in Affalterbach under the sole ownership of Aufrecht. Erhard Melcher stayed at the second location, a former mill in Burgstall, to deliver engine parts.

Mainly for the modern Mercedes-Benz W126 and Mercedes-Benz W201 models, AMG was producing a range of unofficial upgrade and accessories packages, although there were no official tie-ups until the mid '80s, when AMG started to supply the company with aftermarket alloy wheels and styling products.

To take advance of the DTM race successes, official AMG-Mercedes models were developed in the 1990s. Since the Mercedes-Benz takeover, AMG sales have risen over 500%.

AMG also provides safety cars for the FIA Formula 1 World Championship.

 

Source: Wikipedia