- Jan 7 Impeachment trial of President Bill Clinton begins in the US Senate.
- Feb 12 US President Bill Clinton acquitted by the Senate in his impeachment trial
- Mar 29 The Dow Jones Industrial Average closes at 10006.78 - above the 10,000 mark for the first time ever
- Apr 7 The World Trade Organisation rules in favor of the United States in its long-running trade dispute with the European Union over bananas
- Apr 20 Columbine High School massacre: Eric Harris and Dylan Klebold kill 13 people and injure 24 others before committing suicide at Columbine High School, Colorado
- May 27 The International Criminal Tribunal for the former Yugoslavia indicts Slobodan Milošević and four others for war crimes and crimes against humanity committed in Kosovo
- Oct 12 The Day of Six Billion: the proclaimed 6 billionth living human in the world is born
- May 18 "Millennium" 3rd studio album by the Backstreet Boys is released - one of the best-selling albums of all time, over 30 million copies sold
- Aug 31 "Fly" 5th studio album by Dixie Chicks is released (Grammy Award Best Country Album 2000, Billboard Album of the Year 2000)
- Nov 8 Tenor Andrea Bocelli releases his "Sacred Arias" album, the world's best-selling classical album by a single artist
- May 3 Stephen Hendry defeats Mark Williams 18-11 to win the World Snooker Championship for a record seventh time.
- Jul 25 86th Tour de France: Lance Armstrong wins 1st of 7 consecutive Tour de France titles but is later disqualified for drug cheating
- Jul 27 Tony Hawk is the first skateboarder to land a "900"
Kosovo War: NATO commences air bombardment against Yugoslavia, marking the first time NATO has attacked a sovereign country.
On March 24, 1999
NASA loses radio contact with the Mars Polar Lander moments before the spacecraft enters the Martian atmosphere
On December 3, 1999