We present a series of patients who developed cellulitis following axillary lymph node dissection for carcinoma of the breast. Bacterial cultures were not helpful in making a diagnosis for the majority of the cases. The clinical scenario of upper extremity cellulitis after axillary dissection mimics the presentation of cellulitis in the lower extremity. Until diagnostic methods or treatment advances can eliminate the indications for axillary lymphadenectomy, many women treated for breast cancer will be at long-term risk for the development of cellulitis due to localized immune impairment. Patient and physician awareness of this syndrome is the best available tool to prevent secondary exacerbation of lymphedema. Prompt treatment with appropriate antibiotics appears universally successful. Antistreptococcal antibiotics should not be withheld pending results of blood or tissue cultures, since in only a few cases will a pathogen be isolated. Although there are no studies confirming the concept, it is likely that appropriate treatment for lymphedema may reduce the risk of infection.