On this episode: the Iowa caucuses, tax reform, and meet a scholar who studies global poverty reduction. First up, a Brookings expert answers a student’s question about why the Iowa caucuses are so important. This is part of the Policy 2020 Initiative at Brookings. If you have a question for an expert, send a audio file to Second, Hamilton Project Director Jay Shambaugh interviews former treasury Secretary Lawrence Summers, now a professor at Harvard University, about reforming the tax code to raise more revenue in a progressive manner. A transcript of this portion of the episode is available. And finally, meet Matt Collin, one of the new class of David M. Rubenstein Fellows at Brookings. Learn how he came to be a scholar, what he’s focused on now, and his book recommendation. Subscribe to Brookings podcasts  or on , send feedback email to , and follow us and tweet us at  on Twitter. The Brookings Cafeteria is part of the .