Tier-1 mobile operator in Europe Union, serving more than 20 million users. Their challenge is initially, the operator sought compliance with European Union mobile data roaming regulations. After that success, they identified a market opportunity for subscriber services packages and bolt-ons built around usage. They chose Sandvine to overcome this challenge. The Sandvine Policy Engine, which spans the control and data planes, was deployed to provide accurate metering and real-time advice of usage notifications. The results of implementing Sandvine were gaining a multitude of new services that cater to usage habits; subscribers are able to use those services without fear of bill shock. Operator benefited from compliance with European Union regulations regarding bill-shock prevention and roaming charges.