As part of a smokeless tobacco (ST) intervention study, we collected data on tobacco use habits and oral health for 245 male ST users aged 15 to 77. The study sample was identified during routine dental office visits and represents a relatively diverse population of patients. Oral health data collection included grading the clinical appearance of oral mucosal lesions using Greer and Poulson's classification system, as well as identifying and recording the primary anatomic location of ST placement. Results show that 78.6 percent of ST users had observable oral lesions, 23.6 percent of which were in the most clinically advanced category (degree III). Of the lesions noted, 85 percent were in the same location the patient identified as his primary area of smokeless tobacco placement. In a comparison sample of 223 non-ST-users with the same age distribution, only 6.3 percent had observable lesions. A multiple logistic regression model for ST users showed that lesion presence and severity were most significantly related to current frequency of ST use.