Willem Adolph Visser 't Hooft (20 September 1900 – 4 July 1985) was a Dutch theologian who became the first secretary general of the World Council of Churches in 1948 and held this position until his retirement in 1966.

In 1925, while on his first trip to the United States with John R. Mott, he became interested in the "social gospel" movement.

[1] His apartment in Geneva, Switzerland became the meeting place for members of the German Resistance against the Third Reich between March and April 1944.

[2] Hilda Monte and Hannah Bertholet were among the 15-16 people from countries all over Europe who met to discuss international resistance to Nazism.

[1] In 1961, Time magazine did a cover story on Visser 't Hooft[3] and the World Council of Churches.