The kingdom of Saudi Arabia, ruled by the Al Saud family since its founding in 1932, wields significant global influence through its administration of the birthplace of the Islamic faith and by virtue of its large oil reserves. Close U.S.-Saudi official relations have survived a series of challenges since the 1940s. In recent years, shared concerns over Sunni Islamist extremist terrorism and Iranian government policies have provided some renewed logic for continued strategic cooperation. Political upheaval and conflict in the Middle East and North Africa appear to have strained bilateral ties, but the Trump Administration has stated its intent to strengthen ties to the kingdom. Successive U.S. Administrations have referred to the Saudi government as an important partner, and U.S. arms sales and related security cooperation programs have continued with congressional oversight and amid some congressional opposition. Since 2009, the executive branch has notified Congress of proposed sales to Saudi Arabia of major defense articles and services with a potential aggregate value of more than $119 billion. The United States and Saudi Arabia concluded formal arms sale agreements worth more than $58 billion, from FY2009 through FY2015. Since March 2015, the U.S.-trained Saudi military has used U.S.-origin weaponry, U.S. logistical assistance, and shared intelligence in support of military operations in Yemen. Some Members of Congress have expressed concern about Saudi use of U.S.-origin weaponry, skepticism about Saudi commitment to combating extremism, and doubts about the extent to which the Saudi government shares U.S. priorities. Nevertheless, U.S.-Saudi counterterrorism ties reportedly remain close, and Saudi leaders have taken action against the Islamic State at home and abroad. In parallel to close security ties, official U.S. concerns about human rights and religious freedom in the kingdom have in part reflected deeper concerns for the kingdom’s stability. Saudi activists advance limited economic and political reform demands, continuing trends that have seen Saudi liberals, moderates, and conservatives press for domestic change for decades. While some limited protests have occurred since unrest swept the wider region in 2011, clashes involving Saudi security forces have not spread beyond certain predominantly Shia areas of the oil-rich Eastern Province. The Obama Administration endorsed Saudi citizens’ rights to free assembly and free expression. Saudi leaders reject foreign interference in the country’s internal affairs. The death of King Abdullah bin Abd al Aziz in January 2015 brought to a close his long chapter of national leadership. His half-brother King Salman bin Abd al Aziz assumed the throne and has moved to assert his authority at home and pursue Saudi prerogatives abroad. Succession arrangements have attracted particular attention in recent years, as senior leaders in the royal family have passed away or faced reported health issues. A series of appointments and reassignments since 2015 has altered the responsibilities and relative power of leading members of the next generation of the Al Saud family, the grandsons of the kingdom’s founder. U.S. policy makers have sought to coordinate with Saudi leaders on regional issues and help them respond to domestic economic and security challenges. Saudi authorities are attempting to reorient and revitalize the nation’s economy, while streamlining public expenditure. Shared security challenges have long defined U.S.-Saudi relations, and questions about Saudi domestic and foreign policy may become more pertinent as leadership changes occur in the kingdom and conflicts and competition continue in the Middle East region. Saudi leaders’ assertiveness in confronting perceived threats and the effects of their sharpening tensions with Iran could affect U.S. security interests, including with regard to Yemen, Egypt, Bahrain, Syria, Lebanon, and Iraq.