Since publishing our first India Sector Review, Community Safe Water Solutions, in 2014, a report that assessed the service delivery gap in safe water supply and documented the potential for Small Water Enterprises (SWEs) to provide sustainable safe water supply in quality affected habitations in rural India, we have seen Small Water Enterprises (SWEs) gain traction in the country.Increasingly, SWEs have been recognized for the value and benefits they provide as a cost-effective, safe, affordable solution complementary to piped water supply, to address India's drinking water crisis and contribute to achieving Sustainability Development Goal (SDG) 6.1, universal and equitable access to safe and affordable drinking water for all.SWEs are relevant not just to rural, but also to urban India, particularly where increasing urbanization and migration is creating drinking water stress in India's major cities. The situation in urban India, and the role that Small Water Enterprises can play, is detailed in the Urban Sector Review, Drinking Water Supply for Urban Poor: Role of Urban Small Water Enterprises, published in 2016. Drawing from an assessment of the drinking water scenario in four major cities of India, the report reviews the evolving urban landscape and its emerging demands for safe drinking water. Itprofiles potential funding sources and presents the opportunities and challenges that SWE implementers face as they seek to sustain and scale their operations. Lastly, it provides a series of recommendations to move the sector forward.Building on these recommendations, the Policy and Enabling Environment for Small Water Enterprises report, published in 2017, highlighted critical factors that need to be addressed and specific steps to create a more conducive enabling environment for the rapid growth of SWEs in urban India.Advancing these ideas further, and summarizing the seven reports from the 3 year initiative, Small Water Enterprises for Resilient Cities published in 2018 describes how SWEs can provide safe water security affordably to water stressed cities that are coping with dense populations due to increased migration and urbanization.This 2018 Sector Review, Small Water Enterprises to Mitigate the Drinking Water Challenge, ties together the body of work to understand drinking water supply in rural and urban India, and the gap that can be filled by SWEs amid growing water stress and water-quality contamination. It is informed additionally by on ground experience and learnings from our field initiatives in rural and urban India where we have demonstrated the viability of SWEs.The report includes discussions from expert interviews with SWE practitioners such as Fontus Water, Naandi, Sarvajal, WaterHealth India and Waterlife. It calls for further policy and institutional reforms to promote public private partnerships with fair risk management in tenders, and a conducive ecosystem to accelerate expansion of SWEs. Additionally, this report calls for an investment by the Government into Small Water Enterprises to cover capitalcosts and an operating subsidy to enable low pricing in rural areas for providing safe water access to India's population.This report is intended for stakeholders in the water sector including central and state government, state level water supply departments, local water authorities, financing institutions, SWE implementers, NGOs and funding partners who are committed to delivering safe drinking water.