"Why GAO Did This Study The collection of biometrics data, including fingerprints and iris patterns, enables U.S. counterinsurgency operations to identify enemy combatants and link individuals to events such as improvised explosive device detonations. GAO was asked to examine the extent to which (1) DOD's biometrics training supports warfighter use of biometrics, (2) DOD is effectively collecting and transmitting biometrics data, and (3) DOD has developed a process to collect and disseminate biometrics lessons learned. To address these objectives, GAO focused on the Army and to a lesser extent on the Marine Corps and U.S. Special Operations Command, since the Army collected about 86 percent of the biometrics enrollments in Afghanistan. GAO visited training sites in the United States, observed biometrics collection and transmission operations at locations in Afghanistan, reviewed relevant policies and guidance, and interviewed knowledgeable officials. What GAO Recommends GAO recommends that DOD take several actions to: expand leadership training to improve employment of biometrics collection, help ensure the completeness and accuracy of transmitted biometrics data, determine the viability and cost-effectiveness of reducing transmission times, and assess the merits of disseminating biometrics lessons learned across DOD for the purposes of informing relevant policies and practices. GAO"