My research examines the interconnected histories of urbanism and urban development in port cities across South and Southeast Asia. Chapter one examines the effects of the third plague pandemic on the quotidian livelihoods and the built environments of the urban poor across Bombay, Hong Kong, and Singapore. Considering corporeal measures to inspect the bodies and homes of the urban poor and measures to introduce urban ‘improvement’ schemes, this chapter argues that plague sparked a sustained interest in the urban conditions of the poor across British South and Southeast Asia. Chapter two considers the works of the Bombay Improvement Trust, Rangoon Development Trust, and Singapore Improvement Trust through the early decades of the twentieth century and analyses how an imperial urbanism based on a ‘Bombay model’ translated to Singapore and other port cities across the Indian Ocean world. Chapter three considers the consequences of the second wave of ‘indirect’ attacks on urban slums on an evolving imperial urbanism in Bombay, Rangoon, and Singapore. While previous chapters examined the emergence of an imperial urbanism centred on Bombay’s example, chapter four considers the extent to which Bombay remained central to this urbanism during the late 1930s and Second World War. Analysing the divergent consequences of patterns of urban growth in Bombay, Hong Kong, and Singapore throughout the late-1930s, this chapter considers late-colonial efforts to house the urban poor as well as the extent to which the war recast the post-war housing situation. Chapter five contextualises post-war rhetoric of economic and urban development in Hong Kong and Singapore within narratives of pre-war urban ‘improvement’. In connecting pre-war and post-war approaches to accommodating the urban poor, the final chapter considers the reorientation of earlier circulations of knowledge around urban poverty in port cities and its implications for emerging post-colonial regional, national and urban identities.