ObjectiveTo summarize the recently published US Public Health Service report Treating Tobacco Use and Dependence: A Clinical Practice Guideline, which provides recommendations for brief clinical interventions, intensive clinical interventions, and system changes to promote the treatment of tobacco dependence.ParticipantsAn independent panel of 18 scientists, clinicians, consumers, and methodologists selected by the US Agency for Healthcare Research and Quality. A consortium of 7 governmental and nonprofit organizations sponsored the update.EvidenceApproximately 6000 English-language, peer-reviewed articles and abstracts, published between 1975 and 1999, were reviewed for data that addressed assessment and treatment of tobacco dependence. This literature served as the basis for more than 50 meta-analyses.Consensus ProcessOne panel meeting and numerous conference calls and staff meetings were held to evaluate meta-analytic and other results, to synthesize the results, and to develop recommendations. The updated guideline was then externally reviewed by more than 70 experts and revised.ConclusionsThis evidence-based, updated guideline provides specific recommendations regarding brief and intensive tobacco cessation interventions as well as system-level changes designed to promote the assessment and treatment of tobacco use. Brief clinical approaches for patients willing and unwilling to quit are described. Major conclusions and recommendations include: (1) Tobacco dependence is a chronic condition that warrants repeated treatment until long-term or permanent abstinence is achieved. (2) Effective treatments for tobacco dependence exist and all tobacco users should be offered those treatments. (3) Clinicians and health care delivery systems must institutionalize the consistent identification, documentation, and treatment of every tobacco user at every visit. (4) Brief tobacco dependence treatment is effective, and every tobacco user should be offered at least brief treatment. (5) There is a strong dose-response relationship between the intensity of tobacco dependence counseling and its effectiveness. (6) Three types of counseling were found to be especially effective—practical counseling, social support as part of treatment, and social support arranged outside of treatment. (7) Five first-line pharmacotherapies for tobacco dependence—sustained-release bupropion hydrochloride, nicotine gum, nicotine inhaler, nicotine nasal spray, and nicotine patch—are effective, and at least 1 of these medications should be prescribed in the absence of contraindications. (8) Tobacco dependence treatments are cost-effective relative to other medical and disease prevention interventions; as such, all health insurance plans should include as a reimbursed benefit the counseling and pharmacotherapeutic treatments identified as effective in the updated guideline.