Immigration defined as "illegal" is a typical area where the dominant representations differ from social phenomena. Starting from this point, this article deals with two issues. The first is the selective treatment of irregular immigration by receiving societies. Diverse interests and social representations of irregular immigration tend to redefine it in different ways: formal authorization and social recognition should be distinguished, and they can go in different directions. Their intersection determines four cases: exclusion, stigmatization, tolerance, integration. The second, and related, issue is the easier transition to a legal status of some irregular migrants, especially those who encounter some forms of tolerance in receiving societies. Three devices of regularization will be identified and discussed: deservingness; liberal legalization; victimization. In regard to processes of acceptance and legalization, the action of various intermediaries between the receiving societies and irregular immigrants will be highlighted.