&NA;The natural history of cavernous angiomas is poorly understood, and their growth has rarely been documented. We report three cases of cavernous angiomas that grew to large size in 6 years, 2 years, and 2 months, respectively. An initial computed tomographic scan disclosed no abnormalities in one patient and demonstrated two “minimal” lesions in the other two. The mechanisms of growth of these lesions are discussed; subsequent hemorrhages and capsule formation played a major role in their enlargement. (Neurosurgery25:92‐97, 1989)