Even though in vitro diagnostic medical devices (IVDs) occupy only a very small market segment in the healthcare sector, they have a vital role to play. The importance of diagnostics was strongly underlined during the COVID-19 pandemic. In the EU, IVDs are regulated under the In Vitro Diagnostics Regulation 2017/746 (IVDR), with the planned date of application in May 2022. This article gives an overview of IVDs and the regulatory requirements under the IVDR in comparison to the more well-known Medical Device Regulation 2017/745. Considering the similarities in the regulatory landscape and the document requirements of the two regulations, medical writers well versed in mainstream medical devices have the skills and competencies to support IVDs under the IVDR.