The clinical and histopathologic features of 40 cases of sebaceous gland carcinoma include tumors that appeared as a localized lesion (15), diffuse chronic blepharoconjunctivitis (12), recurrent chalazion (eight), and caruncular tumors (two). In three older cases, specimens were submitted with insufficient clinical information. Chronic blepharoconjunctivitis were associated with "pagetoid" involvement of the conjunctive and lid margin. Despite the characteristic pathologic features of sebaceous gland carcinoma, correct diagnosis was given for only 22.5% of tumors on initial pathologic examination. The most common misdiagnoses were basal cell carcinoma (11) and squamous cell carcinoma (ten). Early recognition and diagnosis have substantially reduced tumor mortality. Six (24.0%) tumor deaths were encountered in 25 patients treated prior to 1970. No tumor-related mortality occurred in the 15 patients encountered after 1970.