Yemen’s Arab Spring uprising paralysed that country’s government and shattered its military into hostile factions for over a year beginning in early 2011. This prolonged crisis prevented Yemen’s government, under President Ali Abdullah Saleh, from doing much more than attempting to survive. Saleh used those military units that remained loyal to him for regime protection against anti-government demonstrators and troops who defected to those demonstrators. The uprising subsequently led to a security vacuum that helped allow Al-Qaeda in the Arabian Peninsula (AQAP) and its insurgent force, Ansar al-Shariah, to expand their activities beyond terrorism due to the government’s preoccupation with the Arab Spring. Although AQAP and the Arab Spring demonstrators felt no kinship towards each other, AQAP was more than willing to take advantage of the disorder produced by the uprising. In this new security environment, the militants were able to seize and hold significant amounts of territory in southern Yemen. This book provides an overview and analysis of U.S.-Yemeni relations amidst evolving political change in Yemeni leadership; ongoing U.S. counter-terrorism operations against Al Qaeda in the Arabian Peninsula operatives at large in Yemen’s hinterlands; and international efforts to bolster the country’s stability despite an array of daunting socio-economic problems.