Creches and participatory nurturing groups to improve early childhood development among children aged 0-36 months in rural Jharkhand and Odisha, India Good care, nutrition and opportunities to learn during first three years of life are crucial for children's mental, physical and emotional development. One in four children in the world at risk of not developing to their full potential live in India. Among them, children living in rural areas and those from indigenous (tribal) families are at greatest risk, because they are the poorest.  Creches and parenting groups for children under three and their caregivers are possible strategies to help children get the nutrition, care and stimulation they need in early life. Unfortunately, there is little research on whether, how, and at what cost creches and groups could benefit children's development in rural areas with a large number of indigenous families. We have identified a new source of government funding for creches and groups in Indian states with large indigenous communities; these are called District Mineral Foundations. Funds from District Mineral Foundations are meant to benefit communities affected by mining in 12 states, half of which have large rural and indigenous communities. Funds from District Mineral Foundations could be used to finance creches and groups if our research shows they have benefit for children's development.  In this study, we will adapt an existing model of creches fundable by District Mineral Foundations to make it acceptable to rural, indigenous communities of Jharkhand and Odisha, two states of eastern India where over half of indigenous children are chronically undernourished. We will also adapt a successful model of parenting groups tested in Jamaica and Bangladesh for these same rural, indigenous communities in Jharkhand and Odisha. There are very few tools to measure child development adapted for work with indigenous Indian communities, so we will translate and modify six tools to be able to capture changes in caregivers' knowledge about child development, their interactions with children, and children's own development. Finally, we will test whether creches, either on their own or together with groups can improve the development of children in 60 villages of West Singhbhum and Keonjhar districts, in Jharkhand and Odisha. Twenty of these villages will have creches only, 20 will have creches and groups, and 20 will have normal services provided by government. We will compare the mental, physical and emotional development of children aged two years across these three groups of villages after the interventions.  Throughout the research project, we will engage with advocates for creches and parenting groups at regional and national levels through an existing advocacy network and our own government contacts gained through 10 years of scaling up group interventions in different Indian states. We will aim to increase the number of creches and groups funded by District Mineral Foundations in rural areas of five Indian states with large indigenous communities (Jharkhand, Odisha, Madhya Pradesh, Rajasthan, Chhattisgarh), and where the project's research partners already work. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.