Matt Hancock has announced his ‘Moonshot’ project of achieving population-wide mass testing for Covid-19. He should be congratulated for this shift in strategy. The previous strategy of ‘Test, Trace and Isolate’ relied on people with the virus feeling ill and so taking a test. Those who tested positive would then be called by one of the NHS tracers to ask for their recent close contacts, who the tracer would in turn contact and ask to self-isolate.