What levers can you use to influence those who disagree with you?

Brian is proud to manage the highest performing sales team in his computer hardware company. His group focuses on institutional end- users and has led the firm in sales performance for almost two years now. Brian took over the group 9 months ago and is pleased and relieved that they have been able to continue the winning streak under his leadership. Nevertheless, lately he has been finding himself losing sleep over an ever growing list of questionable practices he has begun to notice. He recognises the intense pressure his folks are under to meet and even exceed their numbers pressures that come from the company on the one hand, and from the intense personal competitiveness that his salespeople bring to their jobs on the other.And then there are the bonuses tied to meeting sales goals, and the desire to please, and thereby retain customers.....