Water and sanitation, as absolute necessities for people, planet and prosperity, are at the very core of sustainable development. In embarking upon the 2030 Agenda for Sustainable Development with a dedicated goal on water and sanitation, credible data is needed to underpin sector advocacy, stimulate political commitment, inform decision making and trigger well-placed investment towards optimum health, environment and economic gains. At present, there are several global initiatives that are monitoring different aspects of the water sector, but a coherent framework is missing. To fulfil this need, Integrated monitoring of water and sanitation related SDG targets – GEMI, is currently being developed, integrating and expanding existing efforts to ensure harmonised monitoring of the entire water cycle. Focusing on aspects related to water, wastewater and ecosystem resources, GEMI complements WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation (JMP) and UN-Water Global Analysis and Assessment of Sanitation and Drinking-Water (GLAAS) efforts on drinking water and sanitation.