Stephen Lundin they call him the big tuna because he wrote a book called FISH. He has been a dishwasher, a business school dean, a winter warming house supervisor, a film maker, a golf caddy, an MBA course designer and teacher of a class called Responsible Leadership and the author of books that have sold in excess of 7 million copies...the Big Tuna  Andrew Sobel  is the leading authority on developing clients for life and building enduring business relationships. He is the most widely published author in the world on the topic of client loyalty, and his bestselling books include Power Questions, All for One, Making Rain, and Clients for Life.