Summary: Although there is general agreement that more investment, including public investment in cases in which the market fails to deliver desired goods and services, would enhance the nation's future economic growth, disagreement persists about the federal role in raising national investment levels. Should that role be limited to cutting the deficit, thereby increasing the capital available for private investment, or should the government take a direct approach and increase its own investment spending? This report (1) identifies key questions that must be answered when choosing and implementing public investment programs and (2) discusses the application of these questions to public investment opportunities, including examples of how they can be applied. It suggests a way to think about investment that can ultimately yield higher living standards for the American people. In developing national budget priorities, decisionmakers can also use this report to identify programs that--whatever their other merits--are unlikely to boost private sector output and economic growth.