Mazda has just celebrated the 40th anniversary of first rotary-engined car and by the end of April 2007 had made 1.97-million rotary engines.
Mazda boss Hisakazu Imaki (representative director, chairman of the board, president and CEO) said: "The rotary engine symbolises Mazda. It was born from a corporate culture that embraces tough challenges.
"We will continue our research and development of the rotary engine in accordance with the 'sustainable zoom-zoom' plan we announced in March 2007.
"The hydrogen rotary engine holds great promise as Mazda's next eco-engine - in fact, test units are running on public roads.
Automakers around the world dedicated considerable R&D resources to rotary-engine development in the late 1950's but most gave up on the formidable technical challenges.
Only NSU and Mazda persevered and on May 30, 1967 Mazda introduced the first dual-rotor, rotary-engined car, the Cosmo Sport.
Mazda got into motorsport in 1968, when Cosmo Sport owners began racing them. The Mazda 787B made rotary engine history in 1991 when it became the first - and so far only - Japanese car to win the 24 Hours of Le Mans.
Rotary racers have also claimed more than 100 wins in each of the Japanese Touring Car series and the International Motor Sports Association (IMSA) series in the US.
The current RX-8 sports car was launched in April 2003, with a new Renesis engine that's more compact more powerful and cleaner-running than its predecessors.
British magazine Engine Technology International voted it "International Engine of the Year" in 2003.
Mazda began developing a hydrogen rotary engine that emits no carbon dioxide in 1991 and in February 2006 the RX-8 Hydrogen RE became the first hydrogen-powered rotary in private use, with seven units on the road in Japan under commercial lease.