Despite some exceptions, the business ethics literature on the moral responsibility of corporations does not emphasize a subject critical to that inquiry: the general nature of corporations. This article attempts to lessen the imbalance by describing three conceptions of the corporation that have been prominent in twentieth century legal theorizing, and by sketching their implications for the moral responsibility of corporations. These three conceptions, at least two of which have counterparts in the philosophical and organizational theory literature, are the concession, (...) aggregate, and real entity theories. The article concludes that the real entity theory is the most plausible of the lot. At least under prevailing tests of moral responsibility, it then contends, corporations-as-real-entities are morally responsible for most of their members' actions. (shrink)