The majority of gang crack sellers, who usually were African-American, did not use crack themselves, but the majority of marijuana, powder cocaine, and heroin sellers did use the drugs they sold. Black gangs that sold rock cocaine on the streets tried to control the rock use of their members. The drugs used usually were alcohol and marijuana. Most had explicit rules about crack use based on their beliefs that crack use by sellers is bad for business, is contrary to gang interests, and sellers should not be their own best customers. These rules seem to be based on a rational decision to maximize profits and to avoid the economic and personal problems that may be result from abuse of the drug. In contrast, Latin groups do not hold similar rules about the use of the drugs they sell. A majority of Latino gang members used the drugs they sold but did not sell crack as they regard it to be a black drug. 5 tables and 33 references