Group identity is viewed as a way to distinguish one group from another. In a competitive, ever-changing environment, group identity is considered increasingly important for a musical ensemble in terms of developing a niche, gaining audience attention, and creating a successful performing team. Thirty professional chamber musicians from "unconventional" or "non-traditional" ensembles were individually interviewed about their personal experiences working within this environment. Results show that group identity emerges in two main ways: members sharing similar characteristics, goals, and objectives, often based on repertoire choice and programming; and the sound or musical aesthetic developed through an interpretation of repertoire, instrumental combination, and the collective skills and knowledge of the musicians. This case study highlights the need for a constant vision and aesthetic concept throughout the lifetime of the ensemble in order for it to be sustainable, yet having to evolve and adapt to changing environmental factors and external influences.