Many social institutions function with rivalry, whether it is the legal adversarial system, the electoral system, competitive sports or the market. The literature on adversarial ethics (with authors such as Arthur Applbaum, David Luban and Joseph Heath) attempts to clarify what is a good behavior in these situations, but this work does not examine if institutionalized rivalry is desirable given its good and bad aspects. According to Monroe Freedman, for instance, the confrontation between lawyers in a trial may help discover (...) important facts about a case. Most economists believe that competition in the market increases economic efficiency. But institutionalized rivalry can also lead to morally wrong acts such as violence, deception or coercion. The aim of this article is to identify the conditions under which rivalry may be more or less desirable in our social arrangements. First, it will be necessary to clarify what is institutionalized rivalry and what is an adversarial scheme. Then, this article will explain what are the generic advantages and problems of adversarial schemes. Finally, this analysis will be used to outline a series of minimal requirements to consider that an adversarial scheme is desirable. (shrink)