A six-year old Quarter Horse mare presented to Cornell University Equine and Farm Animal Hospital for evaluation of dysphagia, nasal discharge, and mandibular lymphadenopathy. On presentation, the mare had clinical signs consistent with a Streptococcus equi ssp. equi (strangles) infection. This diagnosis was later confirmed with positive culture and polymerase chain reaction (PCR). This report describes the diagnosis and treatment of a severe case of strangles as well as appropriate management of a strangles outbreak.