Social wasps are among the most familiar and, alas, the most feared of British insects. In late spring the over-wintered queens sometimes cause alarm as they search for nest sites around our homes, and much later their numerous, smaller, daughters (the workers) commonly fly into rooms. The continuous comings and goings of wasps from under eaves and other sheltered sites betray the presence of a nest. However, these industrious insects have another, beneficial side to their usual stereotyped image.