Many reports of brain-damaged subjects have dealt with the semantics of nouns. By comparison, verb semantics has received little attention in the neuropsychological literature. In this paper we analyze the effects of the actional category of verbs on the performance of two Italian-speaking aphasic subjects in auditory comprehension and oral production tasks. Both subjects are sensitive to the actional value of verbs. In subject GSC, State verbs were significantly more preserved than other verb categories; subject AMA fared better when naming Process verbs than other verb types. These differential patterns of impairment cannot be reduced to effects of abstractness/concreteness or of frequency, and appear to be due to genuine Actionality effects. Results from the present study support the view that actional category information is a fundamental organizational principle of semantic knowledge of verbs in the brain.