According to credit theories of knowledge, S knows that p only if S deserves credit for truly believing that p. This article argues that any adequate credit theory has to explain the conditions under which beliefs are attributable to subjects. It then presents a general account of these conditions and defends two models of cognitive agency. Finally, the article explains how an agent-based approach rescues the credit theory from an apparent counterexample. The article's defense of the credit theory is qualified, however, for one lesson that emerges is that credit theories are theories of subjective justification, not theories of knowledge.