Older adults in senior living communities (SLC) often receive psychosocial treatments to maintain their health and quality of life. Although music therapy is a psychosocial intervention that may address these needs, there is a lack of literature regarding how to build and maintain thriving music therapy departments for older adults at SLC. The purpose of this exploratory interpretivist case study was to understand how music therapy became a thriving department at a SLC. We individually interviewed four music therapists, two music therapy interns, and 10 staff members working at a SLC. We used thematic analysis to analyze transcripts and member checking and trustworthiness to provide credibility to our findings. We identified eight ideas that we categorized into two overarching themes describing how the music therapy team developed and maintained a thriving music therapy department at a SLC: Therapists’ qualities (competence of music therapy team members, growth mindset, helping in and helping out, proactively avoiding burnout) and Departmental values (visibility of music therapy department, communication and education of therapeutic rationales, active role in interdisciplinary care meetings, soliciting input). Findings provide situated context to developing and maintaining a thriving music therapy department at a SLC. Implications, limitations, and suggestions for future research are provided.