The authors report on three cases of cocaine dependence treated with methylphenidate. All patients treated showed marked to dramatic improvement with regard to toxic/abstinence signs and symptoms, craving behavior and other behavioral disturbances associated with heavy and chronic cocaine abuse. The authors explore the possibility that cocaine dependence is associated with pre-existing or resulting psychopathology, particularly mood disturbances. Emphasis is also placed on a predisposing or de novo attention deficit disorder (ADD) as possibly contributing to heavy or continued reliance on cocaine.