During February 1-14, 2002, approximately 100 students presented to a New Hampshire college's student health service with clinical signs of conjunctivitis (Figure 1). The cause of conjunctivitis was initially thought to be viral. However, because of the high number of cases, eye cultures were collected from 12 consecutive students; Streptococcus pneumoniae was isolated from cultures of all 12 students. The medical director of the student health service notified the New Hampshire Department of Health and Human Services about the outbreak and on February 22, the state health department requested assistance from CDC. This report summarizes preliminary results of the investigation of this outbreak, which indicate that an uncommon strain of pneumococcus caused this outbreak and that health-care providers should consider pneumococcus as a cause of conjunctivitis among college students.