The bumper crop of encyclopedias devoted to drugs, drug abuse, and drug policy published during the early 1990s has finally been brought up to date by the 2011 Encyclopedia of Drug Policy. With a time frame that focuses primarily on the 20th and 21st century United States and references events through 2010, this encyclopedia’s entries have been laid out in six general categories: “drugs, laws and policies, organizations and individuals, control strategies and their underlying theories, drugs in select countries, and drugs and other social problems.”