Haagse Hockeyvereniging "Haagsche Delftsche Mixed", commonly known as hdm, is a Dutch professional field hockey club based in The Hague, South Holland.

The club was founded on 8 February 1908, when students from Delft wanted to play hockey with their girlfriends from The Hague. The first men's team won the Dutch national title in 1924, 1930, 1931, 1935, 1941, 1942, and for the last time in 1992. Currently, the first men's team competes in the Dutch second division, the Promotieklasse, the first women's team competes in the Dutch first division, the Hoofdklasse.

In both the competitions 2020-2021 and 2021-2022 the first women's team succeeded to enter the play-offs for the Championship, but did not succeed to reach the finals.

On June 6, 2022, the first men's team promoted back to the Dutch first division Hoofdklasse, after winning a play-offs trilogy (3-1) against SCHC (Stichtsche Cricket en Hockey Club Bilthoven).