By September 2011, there were more than 1,000 amateur roller derby leagues, covering every inhabited continent,[1] with teams in countries such as Canada, Australia, the United Kingdom, New Zealand, Germany, Belgium, Finland, Sweden[2] and Singapore[3] In the UK, the sport is mostly played by women.
[4] Contemporary roller derby has a basic set of rules, with variations reflecting the interests of a governing body's member leagues.
The Women's Flat Track Derby Association (WFTDA), which is used by the majority of leagues around the world.
[5] For example, members of the United Kingdom Roller Derby Association are required to play by WFTDA rules,[6] while members of the Canadian Women's Roller Derby Association are encouraged to join the WFTDA.
[7]