Following a discussion of recent policies for the city centre in Britain, the paper explores the contribution of residential development to aspects of sustainability, drawing on a range of survey evidence in Bristol and Swansea. The residents are frequent shoppers, helping to sustain the local daytime economy. Sustainability goals are also supported because large proportions of residents walk to city centre attractions, and many also to their places of work, showing reduced reliance on the private car. Support for the expanding nighttime economy reflects the age, gender and social class composition of the resident population, with different attractions receiving different levels of support from different social groups, but with younger adults as the mainstay. Sustainability in the city centre context appears best served by a majority of young adult residents, ameliorated by a sizeable proportion of older adults, and an absence of households with children. Grandiose government sustainability aims of creating the truly balanced community which includes many children, should be modified in this local context.