The ATP Finals are the most important professional tennis tournament of the year after the four Grand Slam rounds. There is a rich prize pool up for grabs and the best eight tennis players from the ATP singles and doubles rankings take part. The winner gets from a minimum of 1,100 to a maximum of 1,500 ATP points, halfway between a Masters 1000 tournament (1,000 points) and a Grand Slam (2,000 points).

The Finals, together with the Grand Slams, the Masters 1000 circuit and the Olympic tennis tournament, form the so-called Big Titles.
The tournament has taken on various names over the years: from 1970 (the year of its creation) to 1989 it was called the Masters Grand Prix.

From 1990 to 1999 it was called the ATP Tour World Championship; only since 2000 has it taken on the name of Tennis Masters Cup, keeping it until 2009, the year in which it was changed to ATP World Tour Finals. Since 2017, the current denomination of ATP Finals has been in force.

Given the period in which it is held, usually in the month of November, the tournament is often held in venues that boast indoor fields. From 2009 to 2020 the tournament was played in London.

On 14 December 2018, the Mayor of Turin, Chiara Appendino, officially nominates Turin as the venue for the 5 subsequent editions. The other candidate cities are London, Manchester, Singapore and Tokyo. On 24 April 2019, the designation of Turin as the venue for the ATP Finals from 2021 until at least 2025 was made official.