The Golden Poo, a Japanese good luck charm (playing on the similarity between the words for 'luck' and 'poo' in Japanese) was an eye-catching exhibit at the London School of Hygiene and Tropical Medicine last month in an exhibition drawing attention to sanitation, a major killer of children in developing countries
An Indian boy defecates in a poor neighborhood of New Delhi. Nearly half of India's 1.2 billion people have no toilet at home. More people own a mobile phone, according to the country's 2011 census. Jairam Ramesh, until recently India's rural development minister, urged women not to get married into families that do not have toilets in their homes. Globally, poor sanitation kills more people than HIV and Aids, malaria and measles combined, according to the charity Wherever the Need
A makeshift toilet by the side of a stream in Srinagar, the summer capital of Indian Kashmir. According to Water.org, 780 million people lack access to clean drinking water, often as a result of sewage leaking directly into rivers and lakes
Local loo: a woman outside her new latrine. Burma now has three 'open defecation free' villages, following a community-led sanitation effort by Unicef and the health ministry. Using hands-on visual training and demonstrations, the villages in western Bago Division have stamped out the practice, but 8% of Burma's population still defecate outdoors
An abandoned toilet on the banks of the Mekong river in Laos. The degradation of the water, vital as an economic lifeline for 60 million people, is a great concern for the six Asian nations it flows through
A communal latrine in Kroo Bay in Freetown, Sierra Leone. Cholera is a severe problem in Sierra Leone and elsewhere in west Africa because of open defecation and improper disposal of sewage
There is little privacy in these public latrines in Kroo Bay. There is also a security issue, especially for women needing to go to the toilet at night
How do you provide sanitation in water-scarce, sewage-light areas? Michael Hoffman, of the California Institute of Technology, explains his winning design in the Reinvent the Toilet challenge