Summary In 2021, Aarhus University organizes and hosts the Baltic Sea Science Congress with an expected number of 300-400 participants from all over the Baltic. The BSSC is an interdisciplinary forum for scientists working to improve our understanding and management of the Baltic Sea ecosystem. It attracts researchers working within both basic and applied science and aims at fostering dialogue between scientists and environmental managers. BSSC will attract young scientists by having a forum on the first day of the conference for networking and giving priority to their presentations. The four main days will start with keynote lectures by highly recognized scientists in the field, followed by contributed presentations, poster sessions and specialized workshops for discussing emerging topics.