Daniel Gideon Mazer (born 4 October 1971) is a British director, screenwriter, producer, and comedian. He is best known as comedian Sacha Baron Cohen's long-time writing and production partner, who worked with him on his three unorthodox characters Ali G, Borat, and Brüno. He also co-wrote and co-produced films based on Baron Cohen's characters, such as Ali G Indahouse, Borat, and Brüno.

Mazer attended The Haberdashers' Aske's Boys' School, where he met Baron Cohen. He then read Law at Peterhouse, Cambridge University, and graduated in 1994. While at university, he was an active member of Cambridge Footlights and was vice president from 1993 to 1994. His early work includes production roles on The Word, The Big Breakfast and The 11 O'Clock Show. In 2007, he was nominated for the Academy Award for Best Adapted Screenplay for co-writing the film Borat: Cultural Learnings of America for Make Benefit Glorious Nation of Kazakhstan. He shared his nomination with Sacha Baron Cohen, Ant Hines, Peter Baynham, and Todd Phillips. They ended up losing to The Departed. In 2013, he made his debut feature film directing with the British comedy I Give It a Year. He followed it with the 2016 American comedy Dirty Grandpa. In 2020, he co-wrote the script for Borat Subsequent Moviefilm, for which he was again nominated for the Academy Award for Best Adapted Screenplay and won a Writers Guild Award. He is married to television personality Daisy Donovan, with whom he has two daughters, Maisy and Mini Ivy. Mazer is Jewish. Description above from the Wikipedia article Dan Mazer, licensed under CC-BY-SA, a complete list of contributors on Wikipedia