Edmund Gettier (1963) argued against defining knowledge as justified true belief. Using two examples, he demonstrated that (a) believing a proposition to be true, (b) having justification for that belief, and (c) the proposition in fact being true, do not constitute sufficient conditions for one to be said to know the proposition. The purpose of this paper is to investigate the utility of a behavioral definition of justified true belief. I will define “justified,” “true,” and “belief” in behavioral terms. Then (...) I will present examples of justified true belief that are consistent with these definitions and discuss whether the examples may be said to represent sufficient conditions for knowledge. I make the claim that if the justification is of the right type, justified true belief does equal knowledge to the extent that the behavior results in effective interaction with the environment. Looking at justified true belief behaviorally is useful in that it clears up potential confusion associated with the misuse of the terms. However, behavioral justified true belief is still vulnerable to Gettier cases. (shrink)