This 6-month, double-blind, placebo-controlled trial will enroll 210 participants with current DSM-IV diagnoses of cocaine dependence. Treatment will occur for 8 weeks. Participants will be randomly assigned to receive a single morning dose of low-dose modafinil (200 mg/day), high-dose modafinil (400 mg/day), or matching placebo tablets. In addition, each week participants will receive manual-guided cognitive behavioral therapy at the Treatment Research Center. At the end of the 8-week treatment period, modafinil or placebo will be abruptly discontinued. One week following, an end of medication evaluation will occur. In addition to this, two follow-up evaluations will take place 3 and 5 months after initial randomization. Efforts will be made to continue evaluation of subjects who decide to discontinue the modafinil treatment. Urine benzoylecgonine levels will be used to measure cocaine abstinence. Craving, withdrawal, retention, and adverse events will also be evaluated.