Although commonly used in the treatment of melanoma, sentinel lymph node biopsy has not yet been successfully used to detect lymphatic metastasis of basal cell carcinoma because of exceedingly low rates of metastasis. We describe the use of lymphatic mapping and sentinel lymph node biopsy in a patient after basal cell carcinoma was identified within a lymphatic vessel in the primary excisional specimen. As a result, the patient was found to have clusters of basal cell carcinoma in a sentinel lymph node resected from the right deltopectoral groove. Although metastatic basal cell carcinoma is exceedingly rare, we conclude that sentinel lymph node biopsy may be useful for certain high-risk lesions, such as lesions demonstrating histologic evidence of lymphatic invasion. Further experience is necessary to determine the clinical usefulness of sentinel node biopsy in these patients and its effect on patient survival.