In the European Union, the introduction of the Medical Device Regulation (MDR) 2017/745 in 2021 increased the regulatory requirements for ‘in-hospital’ manufacture of medical devices. Depending on the exact scenario, a hospital manufacturing devices will need to consider applying one of three sets of regulatory requirements defined in the MDR: a reduced set of rules called the ‘health institution exemption’, which can be availed of under certain conditions; rules that apply for the manufacture of custom-made devices; or, exceptionally and most onerously, the same ‘full’ set of rules that apply to commercial medical device manufacturers. The purpose of this discussion is to provide an introductory guide to compliance with the MDR for in-hospital manufacture, highlighting the main regulatory requirements and the factors which determine which of the three ‘routes’ is the most appropriate.