Odisha Environment Congress (OEC) is a flagship programme of HDF-cDAR. Started in 2010 as an annual scientific and civil society event on the environment, the Odisha Environment Congress (OEC) has completed 15 years of its successful journey.. OEC has been providing a unique opportunity to academicians, researchers, scientists, planners, policymakers, students, practitioners, community members and civil society organizations of the State and outside for learning, interaction and dissemination of knowledge and ideas on different themes around the environment. It also provides scope for publication of theme-specific and research-based articles in the proceedings which are released during the main event, besides providing an opportunity for the professionals to present their articles in various technical sessions. The themes of last 15 years were “Environment & Water Resources” in 2010, “Environment & Forest” in 2011, “Environment & Energy” in 2012, “Environment & Agriculture” in 2013, “Environment & Climate Change” in 2014, “Environment: Health and Nutrition” in 2015, "Environment: Water, Sanitation and Hygiene (WASH)” in 2016, “Environment & Sustainable River Basin Management” in 2017, “Environment and Gandhi” in 2018, “Environment and Mining” in 2019,: Environment & Biodiversity” in 2020, “Environment and Pandemic” in 2021 and “Environment and Tribes” in 2022, “Environment and Urbanisation’ in 2023 and "Environment & Coast" in 2024.