W. H. R. Rivers, English anthropologist, neurologist, ethnologist, and psychiatrist (b. 1864)
William Halse Rivers Rivers FRS FRAI ((1864-03-12)12 March 1864 – (1922-06-04)4 June 1922) was an English anthropologist, neurologist, ethnologist and psychiatrist, best known for his work treating First World War officers who were suffering from shell shock in order to return them to combat. Rivers' most famous patient was the war poet Siegfried Sassoon, with whom he remained close friends until his own sudden death.

During the early years of the 20th century, Rivers developed many new lines of psychological research. In addition, he was the first to use a type of double-blind procedure in investigating physical and psychological effects of consumption of tea, coffee, alcohol, and drugs. For a time he directed centres for psychological studies at two colleges, and he was made a Fellow of St John's College, Cambridge. He is also notable for having participated in the Torres Strait Islands expedition of 1898 and his consequent seminal work on the subject of kinship.