This article experimentally studies punishment from unaffected third parties in ten different games. The authors show that third-party punishment exhibits several features that are arguably undesirable. First, third parties punish strongly a decider if she chooses a socially efficient or a Pareto efficient allocation and becomes the richest party as a result. Interestingly, this form of punishment is especially pronounced in women and more left-wing participants. Second, third parties punish strongly a decider if she chooses an equitable allocation and becomes the richest party as a result. Finally, third parties considerably punish passive parties who make no choice, especially if the latter are richer than the third party. Implications of these findings for social theory are discussed. (Contains 1 figure, 6 tables, and 11 notes.)