There are several bodies that control 'professional R/C racing'. You only have to really worry about their rules if you are going to enter into a race that is sanctioned by one of these authorities. You will need to contact the organizer of the said race to find out if it is. IFMAR http://www.ozemail.com.au/~ifmar - International Federation of Model Auto Racing. This is taken directly from their web site: "IFMAR's sole responsibility is to organize rules for World Championship events." EFRA http://www.efra.se/ - European Federation of Radio operated model Automobiles. "...the European Federation of Radio Operated Model Automobiles (EFRA) exist to promote International links within the sport of Radio Control Model Car Racing." ROAR http://www.roarracing.com/ - Remotely Operated Auto Racers. "ROAR is the official U.S./Canadian sanctioning body for racing R/C cars." NORRCA http://www.norrca.com/ - National Organization for Racing Radio Control Autos. "The main purpose in forming NORRCA was to give tracks/clubs and racers much more than they were receiving from their existing sanctioning organization. NORRCA is here to help the tracks/clubs promote their existing facilities, develop their existing operations, give them direction on future endeavors and give the racer an organization that is truly built around the racers needs." BRCA http://www.brca.org/ - British Radio Car Association. "It oversees all aspects of the sport, from setting construction rules to organising British championship events, to selecting the British team for International competitions."