text: We have examined the effects of the synthetic matrix metalloproteinase inhibitor, batimastat (BB-94) and the << angiotensin-converting enzyme >> inhibitor, [[ captopril ]], on metalloproteinase activity of murine Lewis-lung-carcinoma cells (3LL) in vitro, and on local growth and lung metastasis of the same tumor implanted intramuscularly in syngeneic C57BL/6 mice.