Metastasis to the regional lymph nodes and lungs was a fairly common finding in mice with induced primary epidermoid carcinoma of the intercapular and adjacent skin. A sex difference in incidence of metastasis was observed, in which involvement of secondary sites among females exceeded that of the males. The difference suggests that the metastatic spread of epidermoid carcinoma may be related, at least in part, to endogenous female sex-hormone levels. The duration of the carcinogenic exposure and dose of carcinogen, each a factor regulating tumor incidence and induction time, were not directly significant as factors regulating metastasis after induction of locally invasive carcinomas. The relative susceptibility of individual animals to the induction of epidermoid carcinoma of the skin had no obvious relationship to the occurrence of metastasis.