Best Book for Successful Selling

Dr. Rick Farr, with whom I teach a business course at Utah Valley State College, gave a great lecture two weeks ago on sales. He has been a highly successful salesman in his career. I just ordered the book that he said is the best book written on successful selling: SPIN Selling by Neil Rackham. This approach claims that asking the right questions is more important in the selling process than anything else. The SPIN Model is this: