The 1999 ATP World Championship was a men's professional tennis tournament that was played in the hall on carpet. It was the 30th edition of the competition in singles and the 26th in doubles, both of which were part of the 1999 ATP Tour . The individual competition was in the last week of November in 2000 Tennis Dome EXPO on the fairgrounds in Hanover held, the double competition found a week earlier in the Hartford Civic Center in Hartford , Connecticut in the United States instead. It was the last staging of the event, the following year the ATP World Cup - together with the competing Grand Slam Cup - was replaced by the Tennis Masters Cup .
Defending champion in the individual was Àlex Corretja , but this time he could not qualify. In the final, Pete Sampras prevailed against Andre Agassi and won the ATP World Championship for the fifth and last time - with that he was the record holder alongside Ivan Lendl ; Roger Federer was only able to break this record in 2011 when he won the year-end event for the sixth time. In doubles, Jacco Eltingh and Paul Haarhuis were defending champions, but only Haarhuis competed in 1999 with another partner. The winners were Sébastien Lareau and Alex O'Brien , who became ATP world champions for the first and only time with a final victory over Mahesh Bhupathi and Leander Paes .