Torchwood is a British television science fiction and crime drama created by Russell T. Davies and starring John Barrowman and Eve Myles dealing with the machinations and activities of the fictional Torchwood Institute. An initial 13-part series was commissioned by the BBC as a spin-off from the long-running science fiction series Doctor Who.

An in-house BBC Wales production for digital television station BBC Three, it is the first television spin-off of Doctor Who since the undeveloped K-9 and Company series of which only a 1981 pilot exists and the first to be commissioned for a full series. The Canadian network CBC is co-producer of the series, with exclusive rights to broadcast the North American premiere of the show.

The title "Torchwood" is an anagram of "Doctor Who". (The name was used as the "codename" for the new series of Who while filming its first few episodes and on the 'rushes' tapes to ensure they were not intercepted. The name was subsequently used in the series, leading to this spin-off.) BBC Wales Head of Drama Julie Gardner serves as executive producer alongside Davies. The first two episodes of Torchwood premiered on October 22, 2006 at 9pm on BBC Three with all subsequent episodes scheduled to be shown at 10pm every Sunday evening. Each episode is repeated on BBC Two every Wednesday at 9pm.