| Date: | 28 November – 3 December (singles) 13–17 December (doubles) |
| Edition: | 31st (singles) / 27th (doubles) |
| Category: | Tour Championships |
| Champs: |  Gustavo Kuerten |
| Champd: |  Donald Johnson / Piet Norval |
| Main Name: | ATP Finals |
The 2000 Tennis Masters Cup and the ATP Tour World Championships (also known as the Gold Flake ATP Tour World Doubles Championship for sponsorship reasons) were tennis tournaments played on indoor hard courts for the singles event, and outdoor hard courts for the doubles event. It was the 31st edition of the year-end singles championships, the 27th edition of the year-end doubles championships, and both were part of the 2000 ATP Tour. The singles event took place at the Pavilhão Atlântico in Lisbon, Portugal, from 28 November through 3 December 2000, and the doubles event at the KSLTA Tennis Center in Bangalore, India, from 13 December through 26 December 2000.
See main article: 2000 Tennis Masters Cup – Singles. Gustavo Kuerten defeated Andre Agassi 6–4, 6–4, 6–4
See main article: 2000 ATP Tour World Championships – Doubles. Donald Johnson / Piet Norval defeated 
Mahesh Bhupathi / Leander Paes 7–6(10–8), 6–3, 6–4