This study tested the market and revenue potential for Mobile Centrex in the Norwegian business market. Mobile Centrex is a system that allows businesses to change from using fixed line telephones to partially or entirely using mobile phones. The Price & Analysis department at Telenor Mobile conducted a series of studies to determine its potential, starting in the late spring of 2000, just before the product launch. Starting with focus groups with users and decision-makers, an understanding was created on how the market would receive a finished product. This led into a quantitative concept test that determined the size of the market potential, the main drivers and barriers, as well as the adoption rate. An analysis of the first businesses adopting Mobile Centrex was made, determining whether Mobile Centrex positively affected the average airtime minutes per user. Also, the paper discusses whether Mobile Centrex will affect the economy positively of both users and telecom operators.