The rapid urbanisation seen by many countries around the world offers great potential for human development. But this comes with a cost. If the human waste produced by our quickly growing cities is not safely managed, the tragedies of stunting, cholera, and child mortality are almost certain to persist.

Most of the urban discussion, including on urban sanitation, is focused on capital cities. Yet, in less developed countries, more than half of all urban residents live in smaller cities of one million inhabitants or less (UNDESA, 2014). These smaller, but rapidly expanding, cities face specific development challenges, often having weaker political autonomy and more limited financial resources than the capital. As the populations of these smaller cities continue to rise, achieving universal urban sanitation is as urgent as ever. Looking across the whole sanitation chain, we find that the first stage – household containment – is often missing, especially in informal settlements in cities.

But surely the world has already solved these sanitation problems? In this report, we take a step back and ask what enabled cities in the 19th and 20th centuries to improve their sanitation systems. Were their sanitation problems the same that developing cities face today? We use lessons learnt in the historical studies to suggest how progress can be achieved in Tanzania, and possibly elsewhere.