This grant provides ongoing support to Ian Cosden at Princeton University, who is formalizing 'US-RSE', a professional association for research software engineers (RSEs) based in the United States. RSEs are a relatively new role within research organizations and typically combine software engineering expertise with experience in specific research disciplines, a role that has become increasingly important as research teams grow more dependent on software to do their work. Grant funds will allow Cosden and the Steering Committee to scale up US-RSE’s efforts by hiring key staff members, supporting an annual conference, awarding community-driven mini-grants, and upgrading critical organizational infrastructure.