Better management of the economy requires better macroeconomic models that can be used to predict the consequences of this or that economic policy choice, proposal, or regime. Better economic models, in turn, require the ability to compare, contrast, and evaluate the predictions of various models across a variety of scenarios. How do professional economists, financial regulators, and central bankers compare one macroeconomic model to another? As it turns out, they don’t. Not only are there no widely accepted ways to compare models, there is little agreement about what criteria make one model better than another. Enter economist Volker Wieland, who is approaching this problem head-on. Collaborating with a wide network of economists in Europe and the U.S., Wieland has developed what he calls the Macro Model Database (MMD), a software platform that can upload, store, and run different macroeconomic models, allowing researchers to confront models with the same historical or synthetic scenarios and compare the predictions subsequently produced. Funds from this grant support a project to make the Macro Model Database fully open source, documenting and disseminating the underlying code to any expert interested in using it. By making it easier for researchers to upload and explore models, Wieland and his team (including Stanford economist John Taylor) plan to double the number of models available on its platform. Additional grant funds support the establishment of a research network based at the Center for Economic Policy Research (CEPR) in London to further promote the MMD’s use within the research community.