The Association of Tennis Professionals (ATP) was founded in 1972 to protect the interests of male professional tennis players and has been the organiser of the main worldwide tennis tour, known as the ATP Tour, since 1990.

The WTP (Women's Association of Tennis Professionals) was set up in 1973 to preform the same role for professional ladies.

Competitions which are controlled by the ATP are the Australian open, the French open, Wimbledon and the US open.

There are seven categories of tournaments belonging to the ATP Tour: the Tennis Masters Cup, the Tennis Masters Series Tournaments, the International Series Gold Tournaments, the International Series Tournaments, the Challenger Tournaments, the Satellite Series Circuits and the Futures Tournaments.

The ATP has developed an ART race, this is where professional rankings come from, they define the ART race as, “an easy-to-understand, simple-to-follow annual race from season start to season end. Every player starts at Zero at the beginning of the year and the player who accumulates the most points by season's end is the World number 1” it is “the mathematical method of ranking male professional tennis players on a calender-year basis”.

Rodger Federer has won the number one position for the past three years and is currently in the lead with regards the 2007 season. He has been in the 1st position for 161 weeks now, Pete Sampras hold the title for most weeks at number one with 286 weeks in pole position.

If you are looking for tickets to any of the events run by the ATP find them here, along with all the major events in the tennis calender.