Allen Klein (born April 26, 1938) is a pioneer in gelotology and the therapeutic humor movement. In 1974, Klein's wife was only 34 years old when she died of liver disease, and the aspect where she had kept her sense of humor all the way to the end inspired Klein to give up his previous career as a theater and television scene designer and to study human development. Klein is an American author and lecturer on the stress relieving benefits of humor and on gallows humor. Among other positions, Klein was the 2005-2006 president of The Association for Applied and Therapeutic Humor.
