Two of the Big Four accounting firms, PwC and Deloitte have bought strategy consulting firms Booz & Company and Monitor respectively. The big IT companies have their own strategy or business consulting division. After showing how to describe and measure strategy in Strategy Maps, Kaplan and Norton have recently published The Execution Premium and their company Palladium's tagline is, "Executing strategy." Troux, maker of enterprise portfolio management software, blogs "Strategy and Execution Belong Together." And, the oil drilling model, while strategy-driven, eventually enables purposeful process execution.