Ten cell lines of human squamous carcinomas of the tongue and larynx have been established from surgical specimens removed from 36 unselected patients, in order to provide systems for investigating the invasive and tissue-destructive capacity of squamous carcinomas of the head and neck. The morphology, ultrastructure and growth characteristics of the 10 lines are described. Detailed cytogenetic analysis of the first 4 lines indicates that each is karyotypically unique, with no evidence of cross-contamination. Nine of the 10 cell lines secrete immunoreactive beta human chorionic gonadotrophin (beta-hCG) in the culture medium. No correlation was demonstrated between the ability of the cell lines to secrete plasminogen activator and their capacity to grow in soft agar or as xenografts in immune-deficient mice.