This is a ‘work-in-progress’ essay. I am making an inventory of eighteenth-century Scottish Catholic correspondence with ARCANE, a database management system which, once the letters are processed, will enable me to give a material representation of this correspondence and of the networks, both human and epistolary, which it reveals. My hypothesis is that links of all kinds – the correspondence itself to start with – enabled the Scottish Catholic community to weather the penal laws in the eighteenth century. What the mission needed most was money and priests; both came from outside Scotland, which is why I have decided to deal with the continental network first.