There is a cogent moral, social and economic argument for investing in achieving equity in the health care of Indians. Recent rapid economic growth provides for a unique opportunity to increase financial commitments to support the public health system and health systems research. India can also draw on the knowledge capital of its booming technology sector to innovate and strengthen the development of health information systems, which has already begun (see Lancet paper on HIS). Furthermore, there is the opportunity to harness the capability of the domestic pharmaceutical industry by inducing it to take greater responsibility for delivering equity in health care. We have suggested principles to guide this vision. The next step is translating these into real and practical policies and effectively implementing them, and the Call to Action takes up this challenge. Yet, this focus on the role of the health system needs to be placed within the broader and bigger context of the social determinants of health, and tackling the root causes of social disadvantage. In this way, a health system built on a strong foundation of public health and primary care must be synergized with public policies that promote critical intersectoral approaches. Improved water and sanitation, food security, poverty reduction and changes to other structural factors, complemented by a more equitable health system, will help ensure more equitable health for more than a billion people.