The frequency of student misconduct and the characteristics of offenders were studied at Lehigh University, Pennsylvania, from June 1, 1978 to June 1, 1981. Three types of misconduct were examined: harm to others, destruction of property, and academic violations. Misconduct was operationally defined and subcategories were developed where greater precision in classification was needed. The frequency of property destruction and academic violations was relatively constant over the three-year period, but harm to others increased sharply in the 1980-81 school year. A significant proportion of that increase could be attributed to assaults that occurred in or near fraternity houses during the spring 1981 semester. In all categories of offenders, the ratio of men to women clearly exceeded their respective proportions in the university population. Also, students who reported participation in major sports were frequently represented among offenders, especially when assaults or academic violations were involved. As a whole, student offenders tended to have lower entering Scholastic Aptitude (SAT) scores and lower grade point averages (GPAs) than Lehigh males in general. However, when student athletes were excluded from the analysis, the SAT scores and GPAs of student offenders did not differ from the Lehigh University average. Appended material includes (1) classification of categories of misconduct, (2) classification of data on student offenders, (3) supplemental information on the method of data collection, and (4) adjudication patterns in the Student Disciplinary Committee. (Author/SW)