Current world population given here (date in mm/dd/yy format).
Current world urban population given here.
See chart at the bottom of this page.

80% of world population will soon be in urban areas (InfoChange News & Features, India, 2007)

Maps from Worldmapper:  World Population 2000   World Population 2050    
                                            City Living   Urban Slums 

"Out of every 100 persons added to the population in the coming decade, 97 will live in developing countries" (Hania Zlotnik, Director, UN Population Division, 2005).

Planning Sustainable Cities − Global Report on Human Settlements 2009 (UN-Habitat, 2010)

Health and the urban environment: revolutions revisited (iied, 2009)

Population Reports: Meeting the Urban Challenge (Johns Hopkins University, 2002)

India's urban poor are being squeezed for living space (The Guardian, 2008)

Our cities, our health, our future: Acting on social determinants for health equity in urban
settings (WHO Kobe Centre, 2007)

State of the World 2007: Our Urban Future (Worldwatch Institute, 2008). University of Leeds Library catalogue entry.

"Although mega-cities have received most of the attention, conditions in smaller urban areas call for even greater consideration. Contrary to general belief, the bulk of urban population growth is likely to be in smaller cities and towns, whose capabilities for planning and implementation can be exceedingly weak. Yet the worldwide process of decentralizing governmental powers is heaping greater responsibility on them. As the population of smaller cities increases, their thin managerial and planning capacities come under mounting stress. New ways will have to be found to equip them to plan ahead for expansion, to use their resources sustainably and to deliver essential services" [State of World Population 2007, Introduction]. University of Leeds Library catalogue entry.

Trends in urban and slum indicators across developing world cities, 1990–2003 (Habitat International, 2008)

Concentration without Congestion: Policies for an Inclusive Urbanization (Chapter 7 of WDR 2009)

Book: Century of the City: No Time to Lose (Rockefeller Foundation, 2008) − the link gives details of how to apply for a free copy. See especially Chapter 4 "Urban health: Learning from systems that work".

State of World Population 2007: Unleashing the Potential of Urban Growth (UNFPA, 2007) ULL catalogue entry.  ►Multimedia presentation

The Transition to a Predominantly Urban World and its Underpinnings (IIED, 2007)

The State of the World's Cities 2006/7 (UN-Habitat, 2006)  ULL catalogue entry

The Urban Poor in Latin America (World Bank, 2005) − read chapter 3 “Keeping a Roof over One’s Head: Improving Access to Safe and Decent Shelter” and chapter 5 “Keeping Healthy in an Urban Environment: Public Health Challenges for the Urban Poor” (chapter 5 has good info. on urban health disparities).

World Urban Forum III (Vancouver, June 2006)  Background paper

The World Goes to Town: A Special Report on Cities (The Economist, 2007) Listen here. 

The Challenge of Slums (UN Habitat Global Report on Human Settlements, 2003)

Global Experiences on Expanding Services to the Urban Poor (WSP, 2009)

See also:  Slum Upgrading   Water Conservation

Global environmental resources versus world population growth (Ecol. Econ., 2006)

Living in the City: Challenges and Options for the Urban Poor (International Food Policy Research Institute, 2002) − a food-security perspective.

Urban Health Updates (Environmental Health at USAID)

Urban Health Information (Environmental Health Project/USAID webpage)

Urban Growth Management Initiative: Causes and Consequences of Urban Expansion (Williams College, website)

---

World population 1950−2050

Most growth is occurring and will continue to occur in urban areas of developing countries, but in reality it will be in periurban areas.