Research software has become a major asset in academic research. It often is the backbone of existing research methods, enables new research methods, implements and embeds research knowledge, and constitutes an essential research product in itself. Research software must be sustainable in order to understand, replicate, reproduce, and build upon existing research or conduct new research effectively. A change is needed in the way research software development and maintenance are incentivized, funded, structurally and infrastructurally supported, and legally treated. Failing to do so will threaten the quality and validity of research. In this context, more than 50 scientists from various institutions gathered at the Robert Koch Institute in November 2019 for a DFG roundtable discussion on sustainability aspects of research software and to draw attention to the need for funding instruments for the sustainable development and provision of research software. The subsequently published position paper (Anzt et al., 2021) seeks to increase the awareness of political and academic decision-makers on the importance and needs of sustainable research software practices. In particular, it recommends strategies and measures to create an environment for sustainable research software.