Writers of working-class memoirs in the twentieth century recalled the psychological ways that respectable individuals managed their relation to London’s most disreputable streets. The Victorian social cartographer Charles Booth had colour-coded these streets as black on his poverty maps, ascribing not only penury but also criminality to them. Into the twentieth century, locals continued to internalise a mythology of rough versus respectable areas. Yet daily they experienced the untenability of these constructed social divides. Some children living on the blackest streets were successfully sheltered from the corruption around them. Others perceived a porousness between infamous and more decent streets. Over on respectable streets, some children observed their parents’ complicity in ‘fiddles’ – illicit ways of earning cash through small illegal ventures. Here, fathers insisted on their honour, even accusing others of immorality. Such an ethics relied upon an internal management of criminal and respectable codes that were complexly interwoven and shaped by family and community ties.