Book excerpt: As a sequel to his popular KNACK of Selling: face-to-face, Keith Rowe expands his time-tested interpersonal skills material to address the essential elements of successful negotiation. While the principles of negotiation can apply to everything from the relatively frivolous excitement of buying a new digital television to the deadly seriousness of negotiating a hostage release, the real focus here is on the commercial buying and selling role, where the ongoing trading relationship goes hand in hand with securing the deal.The Reader: This is a 'must have' reference for marketing and product managers, trade salespeople, those reseller buyers or purchasing officers who sit across the table from them, and the retail managers and salespeople who ultimately on-sell the proposition to the consumer. It should prove invaluable to anyone involved in the face-to-face challenges of negotiating the passage of products and services through the supply chain.