The concept of possible worlds, originally introduced in philosophical logic, has recently gained interdisciplinary influence; it proves to be a productive tool when borrowed by literary theory to explain the notion of fictional worlds. In this book Ruth Ronen develops a comparative reading of the use of possible worlds in philosophy and in literary theory, and offers an analysis of the way the concept contributes to our understanding of fictionality and the structure and ontology of fictional worlds. Dr Ronen suggests a new set of criteria for the definition of fictionality, making rigorous distinctions between fictional and possible worlds; and through specific studies of domains within fictional worlds - events, objects, time, and point of view - she proposes a radical rethinking of the problem of fictionality in general and fictional narrativity in particular.