In September 2010, the Pennsylvania Department of Health was notified of a cluster of invasive group A Streptococcus (GAS) infections among residents of a skilled nursing facility specializing in neurologic and pulmonary care. The Montgomery County Health Department, the Pennsylvania Department of Health, and CDC conducted an investigation to identify additional cases and GAS carriers, assess risk factors and infection prevention practices, implement control measures, and prevent further infections. The investigators determined that, during October 12, 2009-September 22, 2010, 10 residents at the facility had noninvasive GAS infection, and 13 had invasive GAS infection; two residents with invasive infection died. An additional seven culture-confirmed GAS infections could not be characterized as cases because the residents' symptoms were unknown. Staff members and residents were screened by culture to identify GAS carriers, who were then administered antibiotics. Multiple infection prevention deficiencies were noted at the facility, including ineffective hand hygiene practices among staff members. Education on infection prevention practices was provided, and active surveillance was implemented. Invasive GAS outbreaks in long-term-care facilities often result in high death rates. Long-term-care facilities, including skilled nursing facilities, should investigate single cases of invasive GAS infection and ensure that infection prevention measures are fully implemented.