UpTERN, a study conducted by the Tobacco Etiology Research Network (TERN), was designed to examine trajectories of change in smoking behavior and the emergence of dependence over the course of the freshman year from a large sample of college students. The project included extensive quantitative and qualitative assessments of participants. In the first phase, screener data were collected from 4,690 freshmen entering Purdue University in the fall of 2002. In the second phase, 912 students were enrolled from the 2,001 who reported some prior exposure to smoking cigarettes in the first phase. These students provided extensive baseline information on a web-based assessment protocol administered in the week prior to the beginning of classes in the fall semester. In the third phase, these students participated in a web-based assessment administered for 35 consecutive weeks. Approximately 88% of the sample completed the web-based assessment each week. This report describes the rationale for the project and provides an overview of the constructs targeted across the research. In addition, the research methods, procedures, and assessments are discussed. Findings are reported for day-to-day patterns of smoking as well as alcohol and marijuana use across the 35 weeks of assessment. Finally, selected results from reports using data generated from this project are summarized, including analyses of patterns of smoking over time, associations between daily cigarette smoking and alcohol use, evaluations of the nature of nicotine dependence in low-level smokers, an exploration of early cigarette-use episodes in novice smokers, and a consideration of the role of descriptive and injunctive norms from romantic partners and friends in predicting cigarette smoking over time.