Almost half of the global population lives with inadequate or unsafe water, sanitation or hygiene (WASH) services. The consequences of this situation include negative impacts on individual and public health, the environment and economic production. The WASH sector is linked with other international development sectors and is embedded within complex social, environmental and governance structures. This complexity led us to reflect on how WASH sector practitioners and researchers are applying systems thinking tools and techniques to progress an agenda of sustainable and universal WASH services. From this perspective, we then discuss the near- and long-term future needs of the sector in coming to a comprehensive understanding and application of systems thinking to progress the ultimate aim of universal access to safely managed, accessible and abundant water, sanitation and hygiene services.
