Does this sound familiar: ‘Archiving is complicated and everyone does it differently anyway’. To make sure this does not become an excuse to put off the archiving of archaeological geophysics data altogether, this Guide aims to clarify the issues involved and provide examples and help. It is a tall order which is addressed from two ends. Starting with common knowledge about the way data are collected in archaeological geophysics (Data acquisition) and well known issues with data storage (Documenting and archiving), a systematic and comprehensive analysis of what makes up an Archive is developed The archive and the archiving body), forming the conceptual framework and being explained in considerable detail (Archive files and Comprehensive documentation). Existing Archiving Bodies, even those which only contain ‘thin records’ and not ‘thick archives’ (e.g. the English Heritage Geophysics Database and OASIS) are then mapped with their holdings against this framework (Subsets of documentation) showing which parts of the archiving spectrum they cover. Finally a worked examples shows step-by step how an Archive is compiled (Depositing to archives) for deposition to an Archiving Body so that users will be able to evaluate their own archiving practice and, where necessary, update it.