NIDA supports a drug supply program, which provides controlled substances (including research-grade marijuana) to researchers for scientific purposes.
The marijuana supply program operates pursuant to the "Single Convention on Narcotic Drugs", which requires each Nation to designate a single official source of marijuana for medicinal research.
In the United States, NIDA has been designated the responsible agency.
NIDA contracts with the University of Mississippi to grow marijuana for use in research studies. The University designates a secure plot of land where marijuana crops are grown every few years, depending on demand.
The marijuana is grown, harvested, stored, and made into cigarettes or other purified elements of marijuana to use for research.