For all of us who have been working in water for the last 15 years or more, 2015 was year 1, the target year for the Millennium Development Goals. For many countries, the data showed great progress: from 1990 to 2012, 2.3 billion people gained access to improved water sources and almost 2 billion to improved sanitation.

However, there is no room for complacency—today more than 700 million people, still use unimproved drinking water sources; and some 2.5 billion people unimproved sanitation facilities. The numbers are much worse among the most vulnerable segments of society and in the most remote areas of our world.