Increasingly, the emphasis of health care policy is to tap the potential power of informed consumers to improve health outcomes and the efficacy of health care. Employers and payers, recognizing the essential role that consumers can play in containing costs and improving care, have undertaken initiatives to influence consumers’ behaviour.They have urged consumers to change the way they select and use health care and how they manage their day-to-day health. Attempts have been made to encourage consumers to select high-performing providers, health plans and facilities; choose evidenced-based, cost-effective treatments; collaborate with their providers; initiate and maintain healthy behaviour; and manage their own symptoms and conditions. At the same time, consumers are being asked to assume a greater share of their health care costs than ever before. As a result, choices have become more consequential for patients, in terms of both financial and health outcomes (Herzlinger, 2002; Iglehart, 2002).