In this article, the authors describe a grassroots model for research support and explore the success and evolving directions of this model based on three iterative needs assessments administered by the Librarian and Archivist Research Support Network (LARSN) Steering Committee at The University of Western Ontario. Needs assessments were identified as a critical tool to ensure that LARSN programming is relevant to librarians’ and archivists’ changing research needs. In the first four years of LARSN, three needs assessments were administered: in fall 2007, fall 2009, and spring 2011. The iterative needs assessments aimed to capture how the environment and research needs were evolving over time and the ways in which LARSN might continue to support a healthy and productive research environment. LARSN is faced with challenges that include a diversity of needs within its community, inconsistent participation levels in LARSN initiatives, and the inability to be all things to all people at all times. Still, LARSN is well received overall and rated positively by its community members. This is, in large part, because it has stayed true to its original mission to be needs-driven and responsive.