Groupe URD - partnered with the NGO Toilettes du Monde - conducted the external interim evaluation of Action Against Hunger’s project to “improve access to Water, Sanitation, Hygiene in the yurt areas of Ulaanbaatar, by providing proven and innovative solutions” in Mongolia. This project, established in 2009, aims to improve the poor health conditions of the vulnerable populations of the Ger neighbourhoods. An initial three-year “pilot” phase allowed the problems of this periurban context in an extremely cold climate to be analysed and innovative solutions to be tested, in particular EcoSan and compost toilets. Since May 2012, a second phase has focused on the involvement of local players in the project (Mongolian authorities, the private sector, civil society) by extending the activities tested in the framework of the previous phase. The evaluation by Groupe URD-TDM intended to analyse the quality of the project with a view to proposing possible reorientations, or recommendations to optimise the long-term positive aspect, but also to appraise the added value of this coordination between research work and the evolution of the project.