PAN UK sent a survey to the UK’s top ten supermarkets, asking a range of questions on six topics related to pesticides. All ten supermarkets replied to our survey and we then set about analysing and scoring their responses. Based on their scores, supermarkets were allocated a ranking for each topic of ‘lagging behind’ (1 trolley), ‘could do better’ (2 trolleys), ‘making good progress’ (3 trolleys) or ‘‘leading the way’ (4 trolleys). These scores were then weighted based on how much of an impact that action in that particular area would have on reducing pesticide-related harms.  So, for example, supermarkets scored more points for efforts to phase out Highly Hazardous Pesticides than for becoming more transparent. We then sent each supermarket an outline of what we were planning to publish about them and gave them a chance to respond. See our methodology page for a more detail.