Since the late 1990s, Tanzania has experienced remarkable economic progress. Yet, overall societal benefits have been limited, in particular as to challenging persistent poverty. To counter this shortfall, support for urbanization has been identified as one of three major policy shifts needed in Tanzania. In this paper we will take a critical look at trends in demographic shifts in Tanzania with a particular focus on how to identify processes of urban growth, urbanization and internal migration. In this respect we draw on existing analyses of urbanization produced in the context of the 2009 World Bank report and supplement these with critical examinations of recent household and panel survey data. From these readings we look for a generic portrait of urban growth dynamics in Tanzania during the 2000s. This leads us to an exploration of one of the particular changes in urbanization in this period; the emergence of (smaller) urban centres. Often located in what is designated as rural areas and generally in clear distance of more established city regions and larger agglomerations, these urban centres are only attracting scant attention. This second part of the paper draws on ongoing research exploring the emergence of urban centres in four different regions in Tanzania. In the final discussion we will reflect on demographic shifts and urbanization in Tanzania and how this can be interpreted as one and/or more urban frontier(s).