Objectives: First, to assess the compliance and persistence with stimulants among adolescents with ADHD. Second, to examine the relationship between compliance and persistence with stimulants and the dosage form of the medication. Method: Adolescents with ADHD in the Georgia Medicaid program were followed retrospectively for 12 months in 1995 and their prescription claims data were examined to evaluate for compliance and persistence with stimulant treatment. Results: Of the 1,081 study cohort, 66% consumed only immediate-release stimulants, and 83.6% took the same stimulant during the course of study. The median compliance and persistence was 120 days and 65 days respectively. Logistic regression demonstrated that younger age, being non- blacks, incorporating sustained-release stimulants in the treatment regimen, and making changes in the stimulant predicted compliance and persistence. Conclusions: Compliance and persistence were poor among adolescents with ADHD. Sustained-release stimulants were associated with better persistence with stimulants.