Congress delegated enforcement of substantive drug laws under Title 21 of the U.S. Code to the Drug Enforcement Administration (DEA). In 1984 Congress amended Title 21 to include a new subsection (h) that permitted the Attorney General to shorten the procedure for placing certain drugs into Schedule 1 of the Controlled Substances Act. The Attorney General subdelegated that authority to the DEA. Congress took this action so that designer drugs could be controlled. Designer drugs are substances manufactured to have a chemical structure only slightly different from that of an existing drug but reacting like the existing drug on the mind and body of the user. Designer drugs can be produced by chemists in large quantities at a single location and are usually sold to affluent groups. New variations of controlled substances were being produced faster than drug enforcement officials could identify them. The author provides a legislative history of subsection (h) and describes how a designer drug known as 3,4 methylene-dioxy-methamphetamine (MDMA) was included in Schedule 1 of the Controlled Substances Act. In 1987, the Tenth Circuit Court of Appeals ruled that the temporary scheduling of MDMA by the DEA under subsection (h) was an improper delegation of power by Congress to the Executive Branch. An analysis of the history of delegation of power by Congress to schedule drugs under the Controlled Substances Act concludes that the Attorney General is statutorily barred from subdelegating the power temporarily to schedule designer drugs to any agency. 111 footnotes.