Recognizing the need to include musicians in mainstream wellbeing profiling and to move beyond a focus on debilitating factors of the music profession, this study aimed to understand how professional musicians experience wellbeing in the light of Positive Psychology. Guided by the PERMA model, the goal was to track enhancers and challenges for wellbeing in relation to the model’s five components: positive emotions, engagement, relationships, meaning and accomplishment. Participants included six professional musicians from six activities: solo, orchestral, choral, chamber, conducting and composing. Two interviews were conducted with each participant, separated by two weeks of diary record-keeping. Results point to high wellbeing. A clear sense of self appears as an overarching sustainer of wellbeing and the transition to professional life as the most challenging time regarding musicians’ flourishing. Positive emotions emerged as highly related to musical moments, while varying repertoire and experiencing different ensembles appeared as central sources of engagement. Meaning emerged as linked to the shared nature of music-making, and a sense of accomplishment was built on internal goals and oneness in performance with others. The key processes for positive functioning appeared to involve responses to, and regulation by, relationships. Implications are discussed in relation to the role of holistic training in educational settings.