Abstract: The present invention relates to a system and method for efficiently identifying the sales opportunities in a business-to-business market environment. It provides a computer-implemented predictive sales intelligence system and method for identifying sales opportunities. The present invention is a computer implemented system and method for efficiently identifying reliable purchase pattern profiles through scientific analysis of customer data. It includes a system and method for calculating a customer's purchase profile, clustering customers based on similarity of their purchase profile, and efficiently providing a reliable set of opportunities including lost sales (retention) and cross-selling (wallet share expansion) opportunities. It uses this reliable estimate of sales opportunities to retain and expand wallet share for customers.