Which domains in life produce the greatest potential for regret, and what features of those life domains explain why? Using archival and laboratory evidence, the authors show that greater perceived opportunity within life domains evokes more intense regret. This pattern is consistent with previous publications demonstrating greater regret stemming from high rather than low opportunity or choice. A meta-analysis of 11 regret ranking studies revealed that the top six biggest regrets in life center on (in descending order) education, career, romance, parenting, the self, and leisure. Study Set 2 provided new laboratory evidence that directly linked the regret ranking to perceived opportunity. Study Set 3 ruled out an alternative interpretation involving framing effects. Overall, these findings show that people's biggest regrets are a reflection of where in life they see their largest opportunities; that is, where they see tangible prospects for change, growth, and renewal.