The COVID-19 Winter Plan, published 23 November, relies on three factors to provide the UK with a “route back to normality”: vaccines, treatments and testing. In addition to PCR testing, lateral flow devices are now being rolled out across England and Wales for the rapid testing of certain occupational groups, community testing and as an alternative to self-isolation following exposure to the virus. How well validated have these tests been? Are they accurate enough for their proposed purposes? And how have they performed to date in mass testing trials?