In this paper the authors provide a description of the organisational and professional context of locum work, identify challenges and opportunities for locum educational psychologists and for services where they are employed, and propose a protocol for use by educational psychologists (EPs) working in a locum capacity and for the services employing them. This is based on a review of the relevant literature in this and other professions and from the experience of the first author as an educational psychologist working independently and providing locum cover in several local authority areas in England.