In an important article published in this journal, Dryzek, Bächtiger and Milewicz (2011) champion the convocation of a Deliberative Global Citizens’ Assembly (DGCA). In this article, I aim to further strengthen the case for a DGCA by addressing: (i) why a DGCA is likely to take a long-term perspective in the global interest and (ii) why it is so vital that a global institution should do so. I start by analyzing the nature of the issues requiring global policy. These issues, I will argue, are typically global cooperation problems. Cooperation problems pose two major challenges. The first is to prevent freeriding – i.e. serving one’s immediate interests at the expense of the global interest. The second is to align on an efficient global policy. In both respects, I will argue, a DGCA is a good candidate to yield desirable results (and is likely to do better than current supranational institutions).