Since the dawn of the medical group practice, physician leaders and practice administrators have leaned on financial accounting data for most strategically and managerially important practice performance decisions. The reason why is unassailable; business success is quantified in terms of dollars and cents. The main challenge of relying on accounting data alone for critical decision-making is the conventions and logic of financial accounting and reporting, while useful and required, are not always sufficient. The reason is accounting conventions and reporting can leave a knowledge gulf between results and rational decision-making. Managerial decisions based upon financial accounting results alone require interpretation, interpolation, judgment, and wide tolerances for decision risk.