A key to understanding any society is its informal institutions, which influence both its economy and its politics. In Ukraine, the most important such institution is endemic corruption, which- aside from Russia's campaign against Ukraine's territorial integrity and sovereignty-is the main threat to the nation. Under Viktor Yanukovych, this corruption took three forms: The first had to do with the trade in natural gas; the second involved Yanukovych handing out large infrastructure projects at his personal discretion; and the third was outright stealing from the government. Now that the Ukrainian people have now made a choice for Europe, they will have their best chance to clean up their country's long-corrupt economy and political realm. © 2014 National Endowment for Democracy and Johns Hopkins University Press.