Sir William John Haley, KCMG (24 May 1901 – 6 September 1987) was a British newspaper editor and broadcasting administrator.

In 1918 he began to study journalism, and in 1921 he secured his first newspaper employment at The Times, eventually being stationed in Brussels.

[1] Early in his career on the Manchester Evening News, Haley was found to be too shy to work as a reporter.

He was editor-in-chief of Encyclopædia Britannica from January 1968 until resigning in April 1969 in an editorial dispute over how to adapt the work to new readers.

It was reported that younger executives (including the company's president, Charles E. Swanson) wanted to introduce livelier materials, while Haley favoured the traditional approach and an expansion in size.