EUSEA is an international knowledge-sharing platform and accelerator of innovation in the fields of public engagement. The association addresses experts involved in the design, organisation and implementation of public engagement activities across Europe. The association comprises about 120 members, including universities and scientific institutions, science festival organisations, science centres and museums, municipalities and NGOs. The network has developed from a platform for European science festivals to a collaborative community of public engagement professionals, developing and testing new formats of science communication, building relationships with researchers, policy-makers and stakeholders from scientific institutions, higher education institutions, municipalities and regions. EUSEA members provide experience and knowledge to conduct complex co-creative public engagement and science communication strategies addressing a wide range of target groups. Over the past 20 years, several EUSEA members have developed innovative forms of public engagement activities and formats, such as science parliaments, hackathons, innovation labs, science picnics, citizen science projects or researcher’s nights.