Effective this season, the first game of the NBA regular season begins on either the first Tuesday of November or the last Tuesday of October, and the last game on the third Wednesday of April. The NBA playoffs begin on the third Saturday of April.
Staples Center's first season saw its tenants at two opposite ends of the league: the Lakers finished with a best regular season record of 67–15 and the NBA title, while the Clippers finished 15–67, the worst of the season.
Two active players were killed in automobile accidents within four months of each other. On January 12, Bobby Phills of the Charlotte Hornets was killed as a result of reckless driving while racing against teammate David Wesley. On May 20, Malik Sealy of the Minnesota Timberwolves was driving home from a birthday party being held for Kevin Garnett when his SUV was struck by a drunk driver who had been driving on the wrong side of the road. Phills would have his jersey retired during the season after news of his unexpected death was announced, while Sealy would have his jersey retired after this season concluded.
San Antonio Spurs forward Sean Elliott was sidelined for most of the season while undergoing kidney transplant operations. He successfully returned on March 13, becoming the first player to return following kidney transplant.
The Boston Celtics officially retired their trademark parquet floor on December 22, 1999, after 54 years. The floor would be replaced by a replica combining elements of the old floor and new wooden sections.
Doc Rivers became the first recipient of the NBA Coach of the Year Award to have not led his team to the playoffs. He coached the Orlando Magic to a respectable 41–41 (.500) record, good enough for the 9th seed in the East.
The Miami Heat changed their logo and uniforms added dark red (road), and also dark red (home) side panels to their jerseys and shorts, and moved into the AmericanAirlines Arena in January 2000 (now Miami-Dade Arena).
Teams in bold advanced to the next round. The numbers to the left of each team indicate the team's seeding in its conference, and the numbers to the right indicate the number of games the team won in that round. The division champions are marked by an asterisk. Home court advantage does not necessarily belong to the higher-seeded team, but instead the team with the better regular season record; teams enjoying the home advantage are shown in italics.