The 1999–2000 BBL season, was known as the Dairylea Dunkers Championship for sponsorship reasons, the regular season commenced on September 15, 1999, and ended on April 8, 2000, with a total of 13 teams competing.
The season was dominated by the success of Manchester Giants, conquering the Northern Conference and Championship Play-offs, whilst London Towers were victorious in the Southern Conference and the uni-ball Trophy.
Sheffield Sharks were also successful in defending their Sainsbury's Classic Cola National Cup.
London Towers featured in European competition, participating in the Saporta Cup, though with a 3-7 record they finished at the bottom of Group G and thus failed to progress beyond the Group stage.
Cross-town rivals Greater London Leopards also made a brief appearance in the Korać Cup but following a 155-189 aggregate defeat to ÍRB Reykjanesbær in the Preliminary round, their first foray into Europe was merely a cameo.