Willem "Wim" Kok (Dutch pronunciation: [ˈʋɪm ˈkɔk] ^ⓘ; 29 September 1938 – 20 October 2018) was a Dutch politician and trade union leader who served as Prime Minister of the Netherlands from 22 August 1994 until 22 July 2002. He was a member of the Labour Party (PvdA).

Kok studied business administration at the Nyenrode Business School, obtaining a Bachelor of Business Administration degree, and worked as a trade union leader for the Dutch Confederation of Trade Unions from 1961 until 1976, serving as its chairman from 1972. In 1976 it merged to form the Federation of Dutch Trade Unions, with Kok serving as its first chairman until 1986. In the 1986 general election, Kok was elected to the House of Representatives, taking office on 3 June 1986. Shortly after the election, incumbent leader of the Labour Party Joop den Uyl announced he was stepping down and endorsed Kok as his successor, taking office on 21 July 1986. For the 1989 general election, Kok served as lead candidate, after which he struck a coalition agreement with incumbent Prime Minister Ruud Lubbers of the Christian Democratic Appeal (CDA), forming the third Lubbers cabinet. Kok became deputy prime minister and minister of finance, taking office on 7 November 1989.

For the 1994 general election, Kok served as lead candidate again and, following a cabinet formation, formed the first Kok cabinet, taking office as Prime Minister of the Netherlands on 22 August 1994. For the 1998 general election, Kok served as lead candidate once more, and after another successful cabinet formation, formed the second Kok cabinet, continuing as prime minister for a second term. In December 2001, Kok announced he was stepping down as party leader and that he would not stand for the 2002 general election or serve another term as prime minister. Kok left office following the installation of the first Balkenende cabinet on 22 July 2002.

Kok retired from active politics at 63 and became active in the private and public sectors as a corporate and non-profit director, served on several state commissions [nl] and councils on behalf of the government, and continued to be active as a lobbyist for the European Union, advocating further European integration. Kok was known for his abilities as a manager and negotiator. During his premiership, his cabinets were responsible for several major social reforms, such as the legalization of same-sex marriage and euthanasia, and further reducing the deficit. Kok was granted the honorary title of Minister of State on 11 April 2003 and continued to comment on political affairs as a statesman until his death at the age of 80. He holds the distinction of leading the first purple coalitions as prime minister and is consistently ranked both by scholars and the public as one of the best prime ministers after World War II.

Willem Kok was born on 29 September 1938, in Bergambacht in the Dutch province of South Holland, the son of Willem Kok, a carpenter, and Neeltje de Jager.

After completing his studies in business at the Nyenrode Business Universiteit, he started his career in 1961 at the socialist Dutch Confederation of Trade Unions (NVV), where he was chairman from 1973 until 1982. In 1982, the NVV merged with the Dutch Catholic Trade Union Federation (NKV) to form the Federation of Dutch Trade Unions (FNV), of which he served as chair until 1986. In this position, he helped negotiate the Wassenaar Agreement.

Kok was elected to the House of Representatives on 3 June 1986, after the 1986 general election. Soon after the election Joop den Uyl, the leader of the Labour Party and the party's parliamentary leader in the House of Representatives, announced that he was stepping down after serving twenty years as party leader. Kok was elected to succeed him and became party and parliamentary leader of the Labour Party in the House of Representatives on 21 July 1986, serving as opposition leader during the parliamentary period of the second Lubbers cabinet.

Kok led his party in the 1989 general election. The Labour Party lost three seats, but the following cabinet formation resulted in a coalition agreement with the Christian Democratic Appeal (CDA), which formed the third Lubbers cabinet. Kok entered government for the first time and became both Deputy Prime Minister of the Netherlands and Minister of Finance, serving from 7 November 1989 until 22 August 1994.