In general, the proportion of the population adequately served with environmental infrastructure and services is greater, the wealthier the city or the nation in which it is located, although the quality of governance is also important.
* There is a great range of political structures, with some cities having governments that are more accountable and responsive to urban poor groups than others (see also Devas, 1999). This clearly in¯uences the quality and extent of provision.
* The powers, resources and capacities to raise revenue available to most urban governments are very limited, with higher levels of government controlling most resources and decisions about investment.
* The complex political economy within all the cities, which in¯uences who gets land for housing and whether this gets served by infrastructure and services.
* The capacity of local government policies and practices to increase rather than decrease poverty, for instance through policies or actions that constrain or harm the livelihoods of low-income groups (see Amis and Grant) or evict them from their settlements.
* unsafe, insuf®cient, over-expensive, inconvenient water * unsafe, over-expensive, inaccessible sanitation * inability to obtain land for housing * lack of solid waste collection * lack of health care.
Inevitably, the quality and extent of their provision is in¯uenced by local power structures (including the extent to which low income groups can in¯uence local government policies and resource allocation) and by the relationships between local government Environmental Governance 1013