James Poterba has made important contributions to the economics of taxation and public finance more broadly. Beginning with studies of taxation in the contexts of corporate finance and aggregate saving, his work evolved to consider microeconomic applications in demography and population ageing, tax incentives for retirement saving, portfolio choice, annuitization, housing and state and local fiscal policy. His work illuminates the markets and contexts where taxes do and do not matter empirically for economic outcomes. Poterba’s scholarship is published in a range of outlets, including top-tier general interest journals, field journals and venues serving audiences of non-specialists and policymakers. Throughout his career, he has taken on leadership roles to support students and faculty at MIT as well as the profession as a whole through the National Bureau of Economic Research.