A VAD, or Voluntary Aid Detachment, was a female assistant supplied by the British Red Cross society to aid people during wartime. VADs were trained to provide First Aid and nursing to the injured from 1909, when the British War Office issued a Scheme for the Organisation of Voluntary Aid.

A popular VAD was Violet Jessop, who aided victims of the Titanic disaster.

VADs and the Red Cross also played an especially important role in World War Two, helping prisoners of war.