Loyalty has long been associated with being moral and upstanding, but recent research has begun documenting how loyalty can lead people to do unethical things. Here we offer an integrative perspective on loyalty and its outcomes. We suggest that a variety of bottom-up and top-down psychological processes lead individuals to be loyal to people and organizations they have obligations to, and that these processes operate in ways that reduce the cognitive dissonance experienced when loyalties conflict with each other or with other moral principles. In this article, we articulate what loyalty is, describe the typical objects of loyalty, explain the mental processes involved in navigating loyalty dilemmas, and end by offering an integrative perspective that illuminates why loyalty leads to both ethical and unethical outcomes and when each type of outcome is likely to occur.