Spin selling methodology
In the 1980s, behavioral psychologist Neil Rackham conducted research over 12 years and 35,000 sales calls, looking at what sellers and buyers actually did during those sales calls. He then correlated that research with sales success.
Rackham was hired by Xerox, Kodiak, Motorola, and others to use that research to help them develop their internal sales methodologies.
In 1988, he founded SPIN Selling, which stands for Situation, Problem, Implication, Need-payoff.