In a world that is increasingly urbanized and threatened by the climate crisis, people are more stressed and disconnected from nature. According to the EU Biodiversity Strategy 2030, “we need nature in our lives” to improve our psycho-physical health and that of the Planet. Indeed, there is a growing recognition that interactions with natural environments have positive benefits on many non-communicable diseases connected to urbanisation, modern lifestyle and working conditions. Green Care means using green spaces to actively promote health, prevent diseases and increase opportunities for social inclusion. Green Care initiatives provide these benefits to people and at the same time they represent opportunities for new businesses and green jobs, sustainable management of natural resources and enhanced cross-sectorial cooperation and innovation. Green Care initiatives are a growing trend, but they are challenged by a lack of innovation capacity, funding, and formal recognition. Green4C connects international researchers and experts from academia and business in the health and environment sectors to support the development of Green Care initiatives. In this context, the project has organised the Green4C hackathons, sprint-like events with the aim to address complex Green Care challenges. These events will take place in 6 different European countries: Austria, Germany, Ireland, Italy, the Netherlands, and Romania. Each hackathon will address a different challenge, specific to the needs of the local Green Care sector. The Green4C hackathons are open to students, experts, professionals, and practitioners interested in nature-based solutions for health and wellbeing. Help us find innovative Green Care solutions, join the Green4C hackathons!