ScienceDaily: World leaders have agreed on the Sustainable Development Goals (SDGs), but arguably Goal six -- the water and sanitation goal -- will have the hardest job building on the work undertaken by the previous Millennium Development Goals (MDGs). A timely special double edition of the journal Environment and Urbanization on "Sanitation and drainage in cities" explores persistent gaps in urban sanitation provision and ways to address them. The water MDG was widely acknowledged as the furthest from delivering...