William Philip Schreiner CMG PC KC (30 August 1857 – 28 June 1919) was a South African barrister and politician who served as the eighth Prime Minister of the Cape Colony from 1898 to 1900, during the Second Boer War.

As prime minister Schreiner favoured negotiation rather than hostilities, to the chagrin of the governor and high commissioner, Alfred Milner, who was actively fomenting war.

His dedication to this ideal was proved by his resignation from the National Convention in order to represent Dinuzulu, who was due to stand trial before a special court set up by the Government of Natal for his alleged treasonous participation in the rebellion of 1906.

[3] Schreiner led the group to London, but the delegation was unsuccessful in its appeal, despite receiving considerable support from the infant Labour Party and other liberal British organisations.

[6] Schreiner was on holiday in England at the outbreak of the First World War and was asked by Gen. Botha to fill the post of High Commissioner for South Africa in London.