Marco Martiniello, of the Fonds National de la Recherche Scientifique Universite de Liège, reviews Alien Policy in Belgium, 1840-1940. The Creation of Guest Workers, Refugees and Illegal Aliens. Belgian alien policy is the focus of the book. It is divided chronologically, beginning with a description of 19th century policy. It then shifts to discourse on immigration as a crucial element to development, though immigration policy was unchanged in the 1920s. A more restrictive policy ensued between 1929 to 1932.