This present paper applies possible-worlds theory – as developed by literary theorists–to an analysis of absurdist drama, a genre that has, to date, been unexplored in these terms. I argue that this framework can prove very useful in the approach to absurdity. I discuss some selected extracts from Pinter’s Old Times, Ionesco’s The Bald Prima Donna, Jacques or Obedience and Rhinoceros, and Beckett’s Waiting for Godot. The analysis is based on Ryan’s (1991) typology of accessibility relations, as well as on her catalogue of types of alternative possible worlds that can be included within a fictional universe (1985). A discussion of the plays in terms of the first typology shows that some partial impossibilities can often be captured by accessibility relations other than logical compatibility, which is typically associated with absurdist drama. I further examine whether it is the relaxation of these relations alone that is responsible for the created oddity. Additionally, in discussing the conflicts within the fictional universe I argue that a further factor for the creation of absurdity lies in the fact that the mismatches fail to move the plot forward, contrary to what happens in other genres.