Of 30 consecutive patients with ocular adnexal basal cell carcinoma, 18 (60%) had at least one additional unsuspected foci of basal cell carcinoma. The patients most likely to have additional basal cell skin cancer were women, those with previous basal cell carcinoma, and those whose eyelid lesions were recurrent, located at the medial canthus, or of the sclerosing cell type. Using a slit lamp helped us to identify suspicious lesions on the face, but we often required the assistance of a dermatologist to diagnose sclerosing lesions. Comprehensive treatment of basal cell carcinomas should include eradication of the initial lesion, examination for coexisting lesions, prophylaxis for solar exposure, and follow-up examinations for recurrent or new lesions.