Since 2009, Greece has grappled with a serious debt crisis. Most economists believe that Greece's public debt, 180% of Greek gross domestic product (GDP),  is unsustainable. The ramifications of the debt have been felt throughout the Greek economy, which contracted by 25% from its pre-crisis level. One in five Greeks is unemployed, with youth unemployment at nearly 50%, and the Greek banking system is unstable. The Greek government has received three financial assistance packages, funded by European creditors and the International Monetary Fund (IMF) in 2010 and 2012, and again by European creditors in 2015. The European Central Bank (ECB) has taken unprecedented policy measures in response to the crisis. Greece concluded the largest debt restructuring with private creditors in history in 2012, in addition to cutting public spending significantly and pledging a host of policy reforms throughout the crisis. Between 2010 and 2013, the crisis in Greece spilled over to Ireland, Portugal, and Cyprus, which negotiated financial assistance packages, and threatened Spain and Italy. While these economies have largely stabilized, the Greek economy remains in crisis. Questions persist about Greece's ability to meet debt repayments, the terms under which European creditors and potentially the IMF would continue to provide support to Greece, the willingness of European creditors to provide debt relief to Greece, and economic reforms that could put Greek public finances on a sustainable path and jumpstart growth. More broadly, the crisis has exposed problems with the institutional architecture of the Eurozone, whose member states share a common currency and monetary policy, but retain national control over fiscal and banking policies. Even as Greek and European leaders have reiterated throughout the crisis their commitment to keeping Greece in the Eurozone, some analysts argue that Greece exiting the Eurozone and adopting a national currency ("Grexit") could provide the government with greater autonomy and flexibility for responding to the crisis. Other analysts argue that abandoning the euro in favor of a national currency would result in a chaotic transition and acutely exacerbate the economic situation in Greece. What started and continues as an economic crisis in Greece has also become one of a broader set of challenges facing the 28-member European Union (EU) that many analysts believe collectively represent the most significant setback in over 60 years of European integration. In Greece and other European countries with struggling economies, public opposition to economic reforms widely viewed as unjustly imposed by other governments and institutions has fueled political instability and growing concerns about the democratic legitimacy of European institutions. Greece has had seven different governments since 2009. Likewise, governments in more prosperous economies, such as Germany's, have faced mounting pressure to end financial assistance to what many voters perceive as profligate governments. Analysts argue that the resulting, fraught debates among European leaders about the appropriate crisis response have heightened political tensions to a degree that could negatively affect the EU over the longer term. Committees in both the House and the Senate have held hearings on the crisis and issues relating to its impact on the United States, and have exercised congressional oversight of U.S. policy responses. In terms of impact on the U.S. economy, Greece is a small economy, accounting for 2% of Eurozone GDP, and the direct financial exposure of the United States to Greece is limited. Many experts agree that potential contagion effects from the crisis in Greece to the broader Eurozone and global economy have largely been contained. While the rate of economic growth is expected to rise in both the Eurozone and in Greece, the legacy of fiscal consolidation and other economic reforms has left the country with declining incomes and an unemployment rate above 20%. Members have also raised questions about the role of the IMF in responding to the crisis, and whether IMF programs put U.S. taxpayer contributions to the IMF at risk. Some Members have also raised the impact the Greek crisis has already and could increasingly have to constrain Europe's effectiveness as a partner for the United States, including on issues such as managing a resurgent Russia and the ongoing conflict in Ukraine. This report provides a brief overview of the crisis, including negotiations between the Greek government, European creditors, and the IMF. It also discusses potential implications of the crisis for the U.S. economy and U.S.-European cooperation on broader strategic and economic cooperation. As Greece prepared during the 1990s to adopt the euro as its national currency, its borrowing costs dropped dramatically ( Figure 1 ). Investors were confident that the Eurozone, with eligibility requirements, a common monetary policy managed conservatively by the European Central Bank (ECB), and rules limiting deficits and debt, would bolster traditionally weaker economies, such as Greece. The Greek government took advantage of lower borrowing costs, with government debt rising from 68% of GDP in 1990 to over 100% of GDP in 2006. However, the influx of capital to Greece and lax enforcement of rules related to public finances did not result in a fundamental change in how the Greek economy was managed or in investments that increased the competitiveness of the economy. Instead, Greek governments used borrowed funds from private investors to pay for government spending and to offset low tax revenue, consistently running budget deficits through the 1990s and 2000s. Greece's crisis was triggered in late 2009, when a newly elected Greek government revealed that its predecessors had been underreporting government budget deficits. Questions about the sustainability of Greek public finances eroded investor confidence and shut the country out of financial markets, when Greece, like many other countries, was using expansionary fiscal policies to recover from the global financial crisis of 2008-2009. Without access to capital markets, uncertainty increased about whether Greece would be able to repay its debt. Investors also started taking a more critical look at the sustainability of public finances in other Eurozone countries, with the crisis eventually spreading to Ireland, Portugal, and Cyprus. There were also questions about possible contagion to Italy and Spain, the third and fourth largest economies in the Eurozone (after Germany and France). More broadly, the debt problems in such countries posed a threat to the European banking system, slowed economic growth, and contributed to increased unemployment in many European countries. Concerned about the systemic risks Greece could pose to the rest of the Eurozone and the broader international economy, other Eurozone governments and the IMF extended two financial assistance packages to the Greek government (in 2010 and 2012) totaling €240 billion (at current exchange rates, about $257 billion). Financial assistance was disbursed in phases, contingent upon fiscal and structural reforms, which have been implemented to varying degrees. In particular, the Greek government has implemented a significant fiscal adjustment, shifting from a primary budget deficit (the deficit excluding debt payments) of 10.1% of GDP in 2009 to a forecasted primary budget surplus of 1.8% in 2017. However, concerns have been raised about the type of fiscal reforms and the pace of structural reforms (for more information, see text box, "To What Extent has Greece Implemented Reforms?"). Additionally, in 2012, Greece restructured debt held by private investors , with private investors taking substantial losses (about 75% on a net present value basis). The ECB also took a number of actions to respond to the crisis in Greece and the broader Eurozone, including purchasing or pledging to purchase bonds in secondary markets (initially through the Securities Market Program [SMP] and later the Outright Monetary Transactions program [OMT]). It also injected more than €1 trillion (about $1.1 trillion) in low-cost, three-year loans (long-term refinancing operations, or LTROs) into more than 800 banks across the Eurozone. The ECB cut interest rates to record lows, and in March 2015, launched a new round of quantitative easing to help stimulate the Eurozone economy. The ECB's actions have been broadly credited with containing the Eurozone crisis and stabilizing Eurozone financial markets. Over the seven years since the onset of the crisis, Greece's debt exposed and exacerbated problems in its banking sector and resulted in a collapse of the economy, far worse than expected at the outset of the crisis ( Figure 2 ). Since 2008, Greece's economy has contracted by 25%, a contraction in economic output that has lasted longer than the contraction during the Great Depression in the United States; unemployment has nearly tripled to nearly 21% (nearly 50% for young people); and public debt has risen from about 100% of GDP to over 180% of GDP, most of which is now owed to other Eurozone governments and institutions. In comparison, other countries in the Eurozone that experienced similar pressures are faring better. Ireland, Portugal, and Cyprus, countries that also turned to the Eurozone and IMF for financial assistance, successfully concluded their programs and have returned to capital markets. The Greek crisis reached a critical juncture during the summer of 2015. The second financial assistance program for Greece was derailed by a stalemate between the government and its Eurozone and IMF creditors. Key disagreements included the economic reforms tied to the disbursement of committed funds, particularly relating to taxes, pensions, and fiscal targets, and potential debt relief from other Eurozone governments in light of its unsustainable debt level and growing public dissatisfaction with austerity. The Greek government has asked for more flexibility on reforms and debt relief from European creditors in light of its unsustainable debt burden and growing public dissatisfaction with austerity; many Greeks viewed the demands of its creditors as humiliating and pointed out that most of the previous bailout money went to repay debts, primarily to French and German banks, and not help the Greek economy. Meanwhile, European creditors, led by Germany, have expressed frustration with Greece's repeated delays in implementing reforms and what is viewed as Greece's lack of regard for abiding by the "rules" of the Eurozone. Elections in January 2015 of a new, far-left, anti-austerity Greek government heightened tensions considerably. In June 2015, the stalemate between Greece and its creditors reached a critical point.