Hundreds of metric tons of cocaine flow annually from South America toward the United States, threatening the security and well-being of U.S. citizens. Since 2000, the United States has provided about $8 billion to countries in the region to disrupt drug trafficking. Most of this assistance went to Colombia to reduce illicit drug production and improve security. In March 2009, the Department of State reported that Venezuela had become a major transit route for cocaine out of Colombia, with a more than fourfold increase in cocaine flow between 2004 and 2007. We determined (1) what is known about cocaine trafficking through Venezuela, (2) what is known about Venezuelan support for Colombian illegal armed groups, and (3) the status of U.S and Venezuelan counternarcotics cooperation since 2002. To address these objectives, we reviewed U.S. counternarcotics reports, assessments, and other documents regarding illicit drugs transiting Venezuela. We also traveled to Venezuela and Colombia to discuss these matters with U.S. and foreign government officials.