•Even people who care about morality often behave dishonestly.•Predictable situational and social forces lead people to behave unethically.•People often cross ethical boundaries without realizing they are doing so.•Morality is malleable, rather than being a stable trait. Cheating, deception, organizational misconduct, and many other forms of unethical behavior are among the greatest challenges in today's society. As regularly highlighted by the media, extreme cases and costly scams are common. Yet, even more frequent and pervasive are cases of ‘ordinary’ unethical behavior—unethical actions committed by people who value and care about morality but behave unethically when faced with an opportunity to cheat. In this article, I review the recent literature in behavioral ethics and moral psychology on ordinary unethical behavior.