Cigarette smoking and nicotine addiction are significant health problems among people with schizophrenia, who smoke at double the rate of the general population. The Agency for Health Care Research and Quality (AHRQ) has recently promoted of evidenced-based practice guidelines for smoking cessation. The AHRQ report summarizes strong evidence that implementation of these practices has clinical impact across multiple populations. However, they have not been tested among persons with schizophrenia. This study tests the impact of implementing the AHRQ guidelines for brief, physician-delivered smoking cessation interventions among people with schizophrenia diagnoses. We hypothesize that when compared to patients receiving treatment at agencies providing standard care, participants receiving treatment at agencies implementing these AHRQ guidelines will have increased attempts to quit smoking; increased readiness to quit smoking; increased smoking cessation/abstinence; and, decreased amount of smoking per day. We also hypothesize that increased duration of intervention and fidelity to guidelines will produce better outcomes. A quasi-experimental study will compare patients receiving care consistent with the AHRQ practice guidelines to patients receiving care that is not consistent with the practice guidelines. Six randomly selected outpatient mental health clinics in Maryland will be enrolled; 3 will be randomly assigned to implement the guidelines immediately (experimental condition) and will implement the guidelines for 12 months, and 3 will delay implementation of the guidelines for six months (control condition) and then implement the guidelines for 6 months. To assess patient outcomes, a randomly selected sample of 63 schizophrenia patients at each clinic (total initial enrollment 378) will be assessed at three time points. Accounting for attrition, we estimate a final sample of at least 50 participants per clinic (150per condition, 300 total) for our first hypothesis. Implementation of practice guidelines will be achieved by intensive training of staff at study sites, ongoing monitoring and assistance, and providing clinic incentives. Fidelity will be closely monitored by a chart review and participant interview. The design suggests a hierarchical data structure, i.e., individual patients are nested within physicians and physicians are nested within clinics. Thus, a multilevel analysis will be utilized to address the research hypotheses. This technique has numerous advantages over traditional multiple regression (or ANCOVA) analysis, including capacity to test hypotheses about cross-level effects (e.g., how AHRQ implementation (a physician-level predictor) affects patient-level outcomes. It also accommodates subjects with missing data, and non-independence of measures within-class (physician or clinic) or intra-class correlation can be estimated and controlled.