This study comprises an initial empirical description of personal and professional characteristics of master genetic counselors-those considered to be experts in the profession. Fifteen peer-nominated genetic counselors, actively engaged in providing clinical services to patients, participated in semi-structured telephone interviews exploring their personal qualities, inspirations, and perspectives on professional development of expertise. Analysis using modified Consensual Qualitative Research methods yielded 7 domains and 33 categories. Findings indicate master genetic counselors have a strong passion for and dynamic commitment to the profession. They also have insatiable curiosity and are life-long learners who are reflective, self-aware, confident, and recognize their limitations. They are authentic and genuine, and consider their personality to be their counseling style. They form collaborative and interactive relationships with patients based on trust, and they have nuanced attunement to the complexity and multiple levels of the counseling process. Master genetic counselors have deep empathy and are inspired by patients and colleagues, and they derive personal meaning from their work. They are affected emotionally by their work, but effectively manage the emotional impact. They view their professional development as ongoing, influenced by colleagues, patients, mentoring, multicultural considerations, and their own family of origin. They also believe professional development of expertise occurs through critical reflection upon the experiences one accrues. Additional findings and their relationship to theory and research, study strengths and limitations, implication for training and practice, and research recommendation are discussed.