In this article, we used ten years of police, crime, and other data from London to investigate the potential effect of stop-and-search on crime. Using lagged regression models and a natural experiment, we show that the effect of stop-and-search on crime is likely to be marginal, at best. While there is some association between stop-and-search and crime (particularly drug-related crime), claims that this is an effective way to control and deter offending seem misplaced. We conclude the discussion by suggesting that, first, from a legal perspective, the key issue is that each and every stop must be justified in and of itself, not because it has some purported broader effect on crime; and, second, from a sociological perspective, our findings support the idea that stop and search is a tool of social control in the broad sense, not crime-fighting in the narrow sense.