This report provides background information on Turkey and discusses possible policy questions and considerations for Members of Congress. U.S. relations with Turkey-a longtime North Atlantic Treaty Organization (NATO) ally-have evolved over time. Turkey's economic dynamism and geopolitical importance underpin its regional and global influence. Although Turkey still depends on the United States and other NATO allies for political and strategic support, and has close economic links with the European Union, its increased economic and military self-reliance since the Cold War allows Turkey relatively greater opportunity for an assertive role in foreign policy. The record of U.S.-Turkey cooperation during the Obama Administration has been mixed. To some extent it mirrors the complexities that past U.S. Administrations faced with Turkey in reconciling alignment on general foreign policy objectives with substantive points of disagreement. Greater Turkish independence of action and continuing political transformation appear to have been mutually reinforcing-with both led for more than a decade by President (previously Prime Minister) Recep Tayyip Erdogan and the Islamist-rooted Justice and Development Party (AKP). However, it remains unclear how Turkey might reconcile majoritarian views favoring Turkish nationalism and Sunni Muslim values with secular governance and protection of individual freedoms and minority rights, including with regard to Turkey's Kurdish citizens. Existing challenges for Turkey and tensions in U.S.-Turkey relations have been exacerbated by a failed coup attempt in July 2016 and the ongoing government response. The vigorous response, accompanied by the Turkish parliament's approval of a three-month state of emergency, seeks to restructure the military and other key institutions and purge Turkey of the influence of Fethullah Gulen. Gulen was formerly a state-employed imam in Turkey, and is now a permanent U.S. resident whose teachings provide foundational inspiration for an array of individuals, educational institutions, and other organizations in Turkey and elsewhere around the world. Turkish officials' claim that Gulen was responsible for the failed coup has fueled anti-American sentiment and conspiracy theories among the media and public opinion. Turkish officials have called for the United States to extradite Gulen, with some saying that a U.S. failure to do so could damage bilateral relations. U.S. officials have stated their willingness to consider any Turkish extradition request under the terms of the applicable bilateral treaty. Bilateral tensions in the failed coup's aftermath have the potential to affect U.S.-Turkey cooperation in countering the Islamic State and more broadly. Effects from some coup plotters' apparent use of Incirlik air base temporarily disrupted U.S. military operations, raising questions about Turkey's stability and the safety and utility of Turkish territory for U.S. and NATO assets.