Virtually any form of multiagent interaction requires reasoning about individual and collective epistemic states. The past two decades have witness a literal explosion of interest on this topic and exciting results have been achieved in the now well-established research area of logic-and-games.

The purpose of this talk is two-fold. First of all we recall a number of key problems in rational interaction, taken mostly from game theory and MAS, which highlight the role of the fundamental epistemic notions of information, belief and knowledge. Despite the unquestionable success of epistemic logics in modelling such notions, all standard formalisms suffer from the much unwelcome problem of logical omniscience. The second part of the talk is devoted to a quick survey of the existing approaches to counter this issue and some initial thoughts about a multiagent-based logical solution to it.