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. Modafinil is a glutamate-enhancing agent. D-amphetamine is a central nervous system stimulant that is approved to treat individuals with narcolepsy and attention deficit disorder. Both modafinil and d-amphetamine may be effective treatments for cocaine dependence. The purpose of this study is to examine the effectiveness of modafinil and d-amphetamine, alone and in combination, in treating cocaine dependent individuals.