Much of the impact of covid-19 during the first wave was determined by decisions made during the early weeks of the pandemic, between January and late March 2020. The seriousness of the threat to the UK was recognised in January when the Government’s Scientific Advisory Group for Emergencies—SAGE—was convened and met on 22 January 2020.97 It is important to record that all decisions taken during those initial weeks were taken in a fog of uncertainty. The UK did not know to what extent covid-19 had entered the country, how many people it was affecting, how quickly it would spread, and what would be the consequences in terms of illness and death. What the UK did know was bleak: from the experience of China and Italy, it was clear that covid-19 was a highly infectious virus, with profound consequences for health, and for which there was no cure nor effective treatments. This meant that the only tools available to affect the spread of the pandemic were isolating people who had contracted the virus and their contacts, and, more generally restricting contacts between people, collectively known as non-pharmaceutical interventions, or NPIs.