In economics and political science, there is evidence from large cross-sectional datasets and field experiments that neighborhoods, villages, cities, and countries with higher levels of cultural diversity have lower levels of generalized trust, lower quality of public goods, and poorer economic performance. However, in social psychology, organizational behavior, and computer science, there is evidence that diverse populations are collectively better able to solve complex problems with creative solutions. The next generation of research, crucial for the globalized world that is undermining homogeneous communities, will utilize experimental research designs (such as those based on natural or quasi-natural experiments, laboratory experiments, and randomized experiments in controlled natural settings) to better understand the mechanisms sustaining underperformance of diverse communities and to identify interventions that enable community members to take advantage of the problem-solving promise of diversity to yield social and economic benefits.