Cocaine is a strong central nervous system stimulant that is widely abused throughout the United Sates. Due to its widespread use, it is important to develop an effective treatment for cocaine dependence. Dopamine transporters (DAT) play an important role in the addictive nature of cocaine; the use of compounds that target DAT may be effective in treating cocaine dependent individuals. Research shows that GBR 12909 has a strong affinity for DAT. The purpose of this study is to determine the safety and potential interaction of GBR 12909 and cocaine in cocaine dependent individuals.