A clinicopathologic study was made of 32 soft-tissue sarcomas of the anterior abdominal wall (ten desmoid tumors and 22 fully malignant sarcomas). Direct invasion of the costal margin or the iliac crest was observed in both types, whereas transperitoneal invasion and metastasis developed characteristically with fully malignant sarcomas. Wide monobloc resection of the abdominal wall, including, where necessary, resection of adjacent bony parts and reconstruction with a prosthetic mesh, satisfactorily controlled local disease in nine of ten patients with desmoid tumor, and in three of four patients with primary operable, fully malignant sarcoma. Adjunctive therapy with radiation and chemotherapy may improve the outcome in patients with recurrent or high-grade sarcomas, but adequate monobloc resection of the primary tumor remains the most important therapeutic objective.