William Samoei arap Ruto (born 21 December 1966) is a Kenyan politician who has been Deputy President of Kenya since 2013. He served as the Acting President of Kenya between 5 and 8 October 2014 while President Uhuru Kenyatta was away at the Hague. He previously served in various ministerial positions including the Ministry of Agriculture and Ministry of Higher Education. He was Secretary General of KANU, the former ruling political party, and MP for Eldoret North Constituency between December 1997 and January 2013. He won the seat in the 1997 Kenyan election after defeating Reuben Chesire. He was appointed to the position of Assistant Minister in the Office of the President by President Daniel arap Moi in 1998. He was promoted to be Minister for Home Affairs in August 2002. He also previously served as the Chairman of the Parliamentary Select Committee on Constitutional Reform in the 9th Parliament.
On 4 March 2013, he was elected as Deputy President alongside President Uhuru Kenyatta. They won on a Jubilee Coalition ticket.