John Danaher (born 1967, Washington, D.C., United States) is a New Zealander Brazilian jiu-jitsu and Mixed Martial Arts instructor. He holds a 4th degree black belt in Brazilian jiu-jitsu under Renzo Gracie, and is an instructor at the Renzo Gracie Academy in Manhattan.[1] Although born in the United States, Danaher grew up in New Zealand, until arriving in the United States in 1991 to study at Columbia University's philosophy PhD program. After arriving in New York, Danaher was introduced to Brazilian jiu-jitsu by a friend at the university, and began taking classes at Renzo Gracie's academy in Manhattan.[2] He continued training at the academy and began to teach classes as well while Gracie was traveling for competition. Since receiving his black belt in the early 2000s, he has been an instructor for several notable jiu-jitsu and mixed martial arts competitors.