The present study shows the importance of research into textual understanding not only in linguistics and psychology, but also in sociologically-oriented trends of the science of literature which, while not centring their activity in interpretation, see in it an interesting object of investigation. The paper sets out a general survey of models of textual understanding and considers some of the critical problems arising from these models from the point of view of a constructivist science of literature. The author then proposes a constructivist criticism of research into textual understanding and constructivist hypotheses concerning it, that serve as the basis for the construction of a model of textual understanding. Finally, textual interpretation is analysed from a constructivist perspective.