Semantic wikis have shown to be feasible systems to enable communities to collaboratively create semantically rich content. They enable users to make the knowledge within the wiki explicit and thus accessible to the application in order to support the users in numerous ways, like improved browsing, or query answering. This also allows the wiki to automatically check the content. In this paper we present a number of approaches in order to provide facilities to ensure the content quality of a wiki, including the application of constraint semantics and autoepistemic operators in ways that are easy accessible for the end user. We discuss the social aspects of such an approach, and argue for the necessity of enabling end users to define the quality checks within the wiki itself.