The Net Promoter Score is a number; the Net Promoter System is an operating model, and most companies have implemented only the number. Fred Reichheld introduced the score in the December 2003 Harvard Business Review article "The One Number You Need to Grow", developed with Bain & Company and Satmetrix, on the…

Net Promoter Score (NPS) is a customer loyalty metric that measures how likely customers are to recommend a company, product, or service to a friend or colleague, calculated as the percentage of promoters minus the percentage of detractors on a single 0–10 survey question.