In many parts of the world the dwelling is a place of production in as well as a place of shelter and a key setting for social reproduction. This paper examines the conceptual and physical boundaries between income generation and domestic activities through the use of empirical data from an informal settlement (Kampung) in Surabaya, Indonesia. Household case studies illustrate how individuals conceptualise their working and living spheres, how boundaries are created and marked, and how changes in activity are accommodated. Linguistic knowledge is used to explore how such conceptions are articulated and expressed. Finally we examine the spatial and social implications and discuss how analysis of the integration of non-domestic activities can inform our understanding of the production, use and meaning of domestic space.