Crime statistics assail us from the front pages of newspapers around the country—and around the globe. As the world's economic systems become integrated, as barriers to trade, travel, and migration come down, criminal opportunities have rapidly expanded across national borders. Transnational crime has become a problem of considerable political urgency that requires long-term attention. The United States and other countries are devoting significant resources to its investigation and control. The National Academies Committee on Law and Justice convened a workshop to elicit ideas about this phenomenon and to discuss the research and information needs of policy officials. This report lays out the full range of research issues and makes useful suggestions for learning more about transnational crime.