A Synthetic Drugs Interagency Work Group (SD-IWG) was directed to oversee implementation of the Action Plan. In the course of meeting four times between October 2004 and April 2005, the SD-IWG was divided into three subgroups, which addressed methamphetamine and chemical control, the diversion of controlled substance pharmaceuticals, and treatment for and prevention of synthetic drug abuse. These subgroups met independently over 6 months and divided their recommendations into three categories: those that are or will be implemented by agencies participating in the SD-IWG, those that require congressional action, and those that require further interagency discussion. Regarding methamphetamine precursor and chemical control, the Action Plan contains recommendations designed to make it more difficult for methamphetamine manufacturers to obtain ingredients, especially pseudoephedrine and ephedrine, which are used in the manufacturing process. These recommendations call for improving chemical control at the international level and in retail and wholesale markets. This report describes the SD-IWG's efforts in these areas. A discussion of efforts to control the diversion of controlled substance pharmaceuticals focuses on reducing doctor shopping and illegal online pharmacies. Efforts in the areas of treatment and prevention have involved expanded support for drug abuse treatment and the creation of a coordinated Federal effort to identify and deal with emerging synthetic drug threats in specific regions. This is called the Early Alert and Response Mechanism (EARM), which will begin its pilot phase in 2006. Several areas will require Federal legislation to provide Federal agencies with the tools necessary to further disrupt the illicit market for synthetic drugs. Appended summary of progress on each of 46 recommendations