The purpose of this study is to assess the efficacy, safety and tolerability of atomoxetine administered once daily in the treatment of adolescents with ADHD after 8 weeks and after 52 weeks

Inclusion Criteria:

• Patients must have ADHD.
• Must be 13-16 years of age.
• Must be able to swallow capsules.
• Expected to achieve score of 70 or more on IQ test
• Willing and reliable to keep appts. for clinic visits and test

Exclusion Criteria:

• Treatment within last 30 days with a drug that has not received regulatory approval for any indication.
• Patients who weigh less than 40 kg or greater than 70 kg.
• Patients with documented history of Bipolar I or II disorder, or psychosis
• Patients with documented history of autism, asperger's syndrome or pervasive developmental disorder