Government regulation of cities in Sweden started with the 1874 National Building Code. In 1907 a Town Planning law was introduced. The praxis that followed was characterized by garden cities and large courtyard housing blocks, adapted to the sites with curved streets in green town plans by the architect P. O. Hallman who was based in Stockholm and influential in international planning debates. Inspired, inter alia by Camillo Sitte and Raymond Unwin, and as a teacher at the Royal Institute of Technology (KTH), he introduced artistic town planning into Sweden. The leading architects designed housing for workers, with simplicity and moderation, typical for the period. In 1926 the Stockholm municipality started a cottage-bureau called the Stockholms stads småstugebyrå (SMÅA), which helped workers to build their own homes by using factory-built units. The SMÅA assisted with organization, materials and instructors. In 1923 tenants created a cooperative housing movement called the HSB. All these efforts were aided by site-leasehold loans with low rate, starting in 1907. This article analyses four town plans by Hallman of importance for introduction of housing for workers: Röda Bergen (1906), Enskede Garden City (1907), Helgalunden (1911), Blecktornsparken (1918), and how they were modified across the twentieth century.