Robbery, and the fear it inspires, has a profound effect on the quality of life in certain urban neighborhoods. Recent advances in criminological research suggest that there is significant clustering of crime in micro places, or "hot spots," that generate a disproportionate amount of criminal events in a city. In this article, the authors use growth curve regression models to uncover distinctive developmental trends in robbery incidents at street segments and intersections in Boston over a 29-year period. The authors find that robberies are highly concentrated at a small number of street segments and intersections rather than spread evenly across the urban landscape over the study time period. Roughly 1 percent and 8 percent of street segments and intersections in Boston are responsible for nearly 50 percent of all commercial robberies and 66 percent of all street robberies, respectively, between 1980 and 2008. Our findings suggest that citywide robbery trends may be best understood by examining micro-level trends at a relatively small number of places in urban environments.