We already know how to save the world. Now we need a strategy to make it happen.

You might be surprised to read that cost-effective solutions already exist for many of the greatest global health challenges. It's true: we already know how to treat the 35 million people living with HIV/AIDS, prevent diarrhea that kills 760,000 children each year, and combat the health risks of alcohol, tobacco, and handguns.

Yet we face an exasperating gap between the health outcomes we can theoretically achieve and those we actually are achieving.

This gap is not caused by a lack of interest or investment. Global health has never before received so much money or such prominence on political agendas. The real underlying problem is that our international system of sovereign states and decentralized control makes it very difficult for us to take collective action against transnational threats and common challenges.

In the absence of a single global government,  we still need effective global governance. Unfortunately, we do not do a very good job of making global decisions, coordinating responses, and enforcing rules. The consequences are serious: when countries do not work together or with non-state actors, it becomes difficult to contain the spread of infectious diseases, stop the flow of falsified medicines, finance the development of new antibiotics, reduce air pollution, or tackle the root causes of poverty.

Attempts to reform our global governance — to collectively address the health threats and social inequalities we now face — have proven difficult. This means that lightning-speed breakthroughs in biology and medicine have not been matched by the changes in global governance necessary to deliver on their promise. Despite a radically different landscape of greater transnational interconnectivity and interdependence, the basic tools of global governance have not advanced much since the Treaty of Westphalia codified state sovereignty in 1648. Confidence in these outdated tools, according to the World Economic Forum, is correspondingly at an all-time low.

There is no doubt that global governance failures can partly be attributed to the considerable time, resources, will, and support needed for reforms. But the other part is that we currently have insufficient knowledge about the reforms that can help achieve objectives that are sought, including the full range of legal, political, social, and economic strategies for global governance and collective action.

In other words, we know a lot about what we can do to improve global health, but we do not know how to organize ourselves across national borders to execute these needed actions.

A number of factors explain why knowledge of global strategy has lagged behind other fields. One is that few researchers with natural interests in global strategy — political scientists, sociologists, and legal scholars — have been trained in the empirical or big-data methodologies that can reveal deep insights beyond that of a curious human mind.

A second is that such fundamental questions require interdisciplinary approaches that have not been supported by traditional academic institutions, incentives, or structures. A third factor is that research tends to be funded and conducted nationally, whereas expertise in this field is thinly spread across countries.

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While global governance of the future  is still to be imagined, trends like population growth, changing environments, and intensifying interconnectedness mean that we need new strategies for effectively managing transnational risks and for reaping each trend 's possible rewards. Continued social progress and planetary survival depend on it. To be successful, these strategies  will have to engage both state and non-state actors (because states alone have proven insufficient),  promote mutual responsibility (because all must be invested in long-term success), and demand multidimensional accountability (because good intentions are not enough). My own research has shown the importance of having strategies that incorporate incentives for those with power to act on them, institutions designed to bring edicts into effect, and interest groups advocating domestic implementation.

The key questions in desperate need of answering, then, are which strategies can actually achieve global collective action, under what conditions, at what cost, and with what risks and tradeoffs?

This requires three lines of social scientific inquiry. First, we need new approaches for synthesizing complex and conflicting evidence about when, how, and why different global strategies can facilitate collective action. Second, we must develop new analytical and empirical methods for evaluating global strategies and use them to draw novel insights about how to best design global initiatives, institutions, and interventions for maximal impact. Third, we need new ways to translate research into evidence-based collective action and train the next generation of strategic thinkers and leaders in these approaches and methods.

Working toward answering these important questions and pursuing these three lines of inquiry will help create a science of global strategy that gives global governors new tools to address the most pressing issues of our time. A healthy future depends on this ability to effectively work together and collectively solve the many overwhelming challenges we will all inevitably face.