Recently, philosophers have charged that Aristotelian-based virtue theories are empirically inadequate because the conception of character in which they are grounded is largely unfounded by findings in psychology. These philosophers argue in favor of situationism, the theory from social psychology that situational rather than dispositional differences among individuals are in large part responsible for human behavior. Situationists dispute the existence of traits that remain consistent across time and diverse situations and argue that features of situations can better explain and predict human behavior. After analyzing the psychological literature and historical cases put forth as evidence for situationism as well as the basic premises grounding arguments against situationism, I make some conclusions about the best responses to situationism. I agree with situationists that Aristotelian-based virtue and character are not quite empirically adequate but disagree that human behavior owes more to situational rather than dispositional determinants. Basing my theory on literature from social psychology, I argue instead that a concept of character grounded in social-cognitive theory is more psychologically realistic and can explain and predict human behavior and ground a character-based virtue theory. A social-cognitive conception of character would highlight the dynamic role between situations and individual psychological factors like beliefs, values, desires and the way that an individual perceives a situation. I sketch out a non-ideal theory of virtue based in a social-cognitive conception of character that is partially dependent on social networks for its maintenance and is fragmented, or contextualized to particular types of psychological situations. However, fragmented and socially dependent virtue is not an optimal type of virtue because it is vulnerable to situational features that place strong psychological pressures on agents to behave in various ways, including ways they would not have normally endorsed. I agree with Aristotelian virtue ethicists that argue that a type of practical wisdom can help to counter the often unwanted and dangerous influence of these strong situations but also maintain that some measure of moral luck is inevitably involved, even in the development of practical wisdom.