On October 17, 2012, the Georgia Department of Public Health (DPH) was notified by the Fulton County Department of Health and Wellness that a local university, the Georgia Institute of Technology, was experiencing a pneumonia outbreak among students. DPH epidemiologists investigated to identify the etiology, find additional cases, and recommend control measures. Respiratory swabs collected from students with pneumonia and tested at CDC using a quantitative real-time polymerase chain reaction (qPCR) assay were positive for Mycoplasma pneumoniae. The university alerted students, faculty, and staff members to the outbreak and recommended prevention measures by e-mail, social media, and posters. A survey administered to students assessed illness prevention behaviors, outbreak awareness, and communication preferences. Eighty-three cases were diagnosed among students during September 1-December 4, 2012, making this outbreak the largest reported at a U.S. university in 35 years. No cases were reported among faculty or staff members. Of the 83 patients, 19 had specimens tested by qPCR, of which 12 (63%) were positive for M. pneumoniae. Despite university communication efforts, approximately half of students surveyed were unaware of the outbreak when surveyed in December. DPH recommendations included implementing university policies that facilitate students staying home and seeking medical care when ill and refining health messages and communication methods to improve awareness of disease outbreaks among students.