Growing up in Dublin, John Kavanagh was a skinny kid who was frequently bullied. After suffering a bad beating when he intervened to help a woman who was being attacked, he decided he had to learn to defend himself. Before long, he was training fighters in a tiny shed and promoting the earliest MMA events in Ireland. And then, a cocky young lad called Conor McGregor walked into his gym... Now, John Kavanagh tells his own remarkable life story - which is at the heart of the global rise of MMA. Kavanagh has become a guru to young men and women seeking to master the arts of combat and earned a reputation as one of the best coaches alive. His portrait of McGregor - who he has seen in his lowest moments and in his greatest triumphs - is a revelation. Win or Learn is an inspiring chronicle of persistence, discipline, and triumph against the odds.