The ATP Masters Series is a series of nine tennis tournaments that are part of the Association of Tennis Professionals (ATP) tour, held annually throughout the year in Europe and North America. The tournaments are mandatory for the top male players on the professional circuit. The series includes some of the most prestigious tournaments in men's tennis after the four Grand Slam events.
The series was introduced in 1996, and was originally known as the Mercedes-Benz Super 9 series from 1996 until 1999, and then the Tennis Masters Series (TMS) from year 2000, before adopting its present name. Although officially launched in 1996 the statistics for Masters Series are widely counted back to the year 1990 (the year when the ATP took over the running of the men's tour).
Results in ATP Masters Series events earn players more world ranking points than regular tournaments, though not as many as Grand Slam events or the year-end Tennis Masters Cup.
Former World No. 1 Andre Agassi holds the record for the most titles with 17.
