The WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation (JMP) monitors progress towards the Millennium Development Goal (MDG) target to halve, by 2015, the proportion of people without sustainable access to safe drinking water and basic sanitation. The JMP publishes a report every two years, which presents an update on the progress made towards reaching the MDG target for drinking water and sanitation. This thematic report on drinking water is designed to complement the main JMP report (WHO/UNICEF, 2010).