This paper is positioned at the intersection of two literatures: partisan polarization and deliberative democracy. It analyzes results from a national field experiment in which more than 500 registered voters were brought together from around the country to deliberate in depth over a long weekend on five major issues facing the country. A pre-post control group was also asked the same questions. The deliberators showed large, de-polarizing changes in their policy attitudes and large decreases in affective polarization. The paper develops the rationale for hypotheses explaining these decreases and contrasts them with a literature which would have expected the opposite. The paper briefly concludes with a discussion of how elements of this “antidote” can be scaled.