In integrational theory, communication is treated as ‘including all processes in which human activities are contextually integrated by means of signs’ (Harris, 1996: 11). Because humans have bodies, it means that a person is always situated, and that the integration of activities is always uniquely contextualized. The signs made to implement a communication process do not pre-exist particular episodes, but are their results. Writing, as a form of communication, involves the integration of activities in relation to the material and spatial installation of the written sign. The written marks have a (relative) permanence that allows them to be re-read, but the reading itself is impermanent and non-reproducible. Thus, each reading involves the creation of new, unique signs. In this essay I will discuss the diversity of activities integrated in reading and illustrate the difficulties involved in distinguishing writing from non-writing, through an attempt made in the 19th century to read markings on the rock at Runamo in Sweden.