Most large and successful cities are faced with the problem of dense informal settlements in central locations that need upgrading. In many, this upgrading should also seek to reduce overcrowding (for instance, by increasing the number of storeys so that the amount of indoor space per person increases and the number of persons per room decreases). Most such informal settlements first developed some decades ago and were on the city’s periphery, but with their very large outward growth they now occupy valuable central locations. Dharavi in Mumbai is one obvious example, with around 600,000 inhabitants and a very large concentration of small and medium size enterprises within an area of two square kilometres.(1) There is also the issue that these settlements’ central locations make the land on which they developed valuable and so of interest to commercial developers. So one critical question is can housing conditions be upgraded in these kinds of central city areas without displacing their populations? Despite the global recession much of urban Asia is facing increasing land pressures, making it increasingly difficult for low-income groups to secure affordable housing (or land on which to build) and often leading to evictions or resettlement. Governments often promote or support the replacement of high density informal settlements (what they usually term “slums”) with high-rise solutions, on the grounds that this promotes the image of a modern city, and often because only high-rise apartment construction can achieve high densities while conforming to local building by-laws. Unfortunately, such solutions suit developers far better than they do those who live in the informal settlements, on sites the developers want. Arif Hasan and his colleagues are challenging the emerging consensus that these sites need to be cleared and rebuilt with high-rises, and the developer-led approach this engenders. Their proposals accept the advantages of density but argue that with the right sort of technical assistance even lower-income communities can achieve higher densities incrementally, with more community control and in ways that are more supportive of local livelihoods and lifestyles. This is supported by studies in different areas of Karachi, one of which is Nawalane in Lyari town. An informal settlement that was regularized in 1976, it has since developed from a low-rise community (with most houses having one or two storeys) to one where most housing is now ground-plus-two to ground-plus-four. Acknowledgement: The study was undertaken by Arif Hasan and colleagues at the Urban Research and Design Cell (URDC) at the Department of Architecture and Planning, NED University of Engineering and Technology, Karachi, and was sponsored by IIED and UNFPA.