Except for third party materials and otherwise stated below, this content is made available under a Creative Commons Attribution-ShareAlike licence ( The material acknowledged below is Proprietary and used under licence for this project, and not subject to the Creative Commons Licence. This means that this material may only be used unadapted within the OpenWASH project and not in any subsequent OER versions.

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Cover image: (top left) © UNICEF Ethiopia in Flickr made available under, (top middle) © David Stanley in Flickr,, (top right) Tesfay Alemseged, (bottom left) Trees for the Future in Flickr,, (bottom right) White Feather Foundation,

Every effort has been made to contact copyright owners. If any have been inadvertently overlooked the publishers will be pleased to make the necessary arrangements at the first opportunity.

Last modified: Tuesday, 23 August 2016, 11:31 PM