The Mathematical Sciences Infrastructure Program aims to foster the continuing health of the mathematical sciences research community by supporting core research, training projects, and conference, workshop, and travel support requests. The program invites projects that support research infrastructure across the mathematical sciences community, including novel projects, training projects, and conference, workshop, and travel support requests. Proposals must demonstrate promise for an impact at the regional or national scale and explain how the activity will go substantially beyond the submitting institution or the location of the event. • The program supports research infrastructure across the mathematical sciences community. • Training projects must include a core research component for trainees in mathematical sciences and demonstrate promise for an impact at the regional or national scale. • Conference, workshop, and travel support requests must include cross-disciplinary activities or have an impact at the national scale. • Proposals must explain the regional or national scale impact of the activity and how it will go substantially beyond the submitting institution or the location of the event.