TIME4CS – Supporting sustainable Institutional Changes to promote Citizen Science in Science and Technology – is an H2020 project funded under the Science with and for Society Work Programme in the call SwafS-23-2020 “Grounding RRI in society with a focus on citizen science”. The project aims at supporting and facilitating the implementation of sustainable Institutional Changes in Research Performing Organizations (RPOs) to promote Public Engagement and Citizen Science in science and technology. Institutional Changes can be defined as a type of change triggered in an organization and characterized by being irreversible, comprehensive, inclusive and contextualized. TIME4CS does not aim at exploring Institutional Changes as a general phenomenon but the project focuses on the specific Institutional Changes needed to embed Citizen Science in RPOs. Therefore, TIME4CS has identified 4 Intervention Areas (IAs) that alone or combined can stimulate the Institutional Changes necessary to promote Citizen Science in Research and Innovation processes: 1) Research, 2) Education and Awareness, 3) Support resources and Infrastructure and 4) Policy and Assessment. TIME4CS analyzes these areas to consolidate the knowledge about the institutional adoption, establishment and maintenance of Citizen Science capacity and to establish a model for Citizen Science expansion through Institutional Changes. For each Intervention Area, TIME4CS has identified an organization that has already undergone some Institutional Changes to promote Citizen Science showing therefore a comprehensive knowledge and expertise. The knowledge of these partners, called Front-Runners, will contribute to the definition of a set of practical actions aimed at paving the way to Institutional Changes, defined Grounding Actions. Front-Runners will interact with and mentor four organizations willing to face the challenge of introducing Citizen Science more and more in their structures. These organizations, defined Implementers, within TIME4CS lifetime will develop tailored roadmaps including a specific set of Grounding Actions to carry out, benefitting of the constant support of Front-Runners. The interaction between Front-Runners and Implementers will take place during the whole TIME4CS lifetime through the development of a mutual learning and knowledge exchange framework designed to support the implementation and the evaluation of the implementation of grounding actions leading to institutional changes with the ultimate goal to encourage public engagement in science and technology.