Europe’s banking union, constituting a supranational pooling of most instruments of banking policy, was established two years ago, in the early hours of June 29, 2012. To a greater extent than was initially realized by most observers, this step marked a watershed in the European crisis by making it possible for the European Central Bank (ECB) to stabilize sovereign debt markets. The banking union will also profoundly reshape and realign Europe’s financial system and institutions, with consequences that will unfold gradually.