The reputation or prestige of a social entity (a person, a social group, an organization, or a place) is an opinion about that entity - typically developed as a result of social evaluation on a set of criteria, such as behavior or performance.

Reputation is a ubiquitous, spontaneous, and highly efficient mechanism of social control. It is a subject of study in social, management, and technological sciences. Its influence ranges from competitive settings, like markets, to cooperative ones, like firms, organizations, institutions and communities. Furthermore, reputation acts on different levels of agency: individual and supra-individual. At the supra-individual level, it concerns groups, communities, collectives and abstract social entities (such as firms, corporations, organizations, countries, cultures and even civilizations). It affects phenomena of different scales, from everyday life to relationships between nations. Reputation is a fundamental instrument of social order, based upon distributed, spontaneous social control.

The concept of reputation is considered important in business, politics, education, online communities, and many other fields, and it may be considered as a reflection of a social entity's identity.