Imagine a world in which the effects of a policy change could be tested in advance. Unintended consequences could be accounted for, mistakes corrected, and new proposals evaluated—all without the tremendous costs of a real-world trial. Experimental economics, pioneered by Vernon Smith (Nobel Laureate, 2002), provides researchers with innovative techniques for determining the effects of policy changes ex ante. Through the use of mechanisms designed to capture the incentive structures of real-world environments, experimenters can reproduce and analyze decision-making contexts. In addition, benchmark comparisons can be made, and controlled replication becomes possible. Experiments cannot perfectly represent the real world, of course, but they allow researchers to test the “what-ifs” of public policy, at a fraction of the cost of real-world trials. As such, they provide a valuable tool for evaluating potential reforms.