Despite the large efforts done by today's companies, keeping customers information organised is becoming harder. Different brands, departments and promotions have the potential to create new valuable information.?The effort required to systematise all this disperse information to better understand customers is becoming increasingly intimidating. In addition, measuring the real impact of many promotional activities is not easy, partly caused by this information dispersion. But it is worth making an effort to integrate data from several sources and measure real effectiveness. This presentation will show how L'Oréal, jointly with DatosClaros and using a metering technology from Netquest, overcome these difficulties. The result: solid data that has become possible to come up with new loyalty pro.