ABSTRACT This study examines the pursuit of occupational legitimacy by Korean tattooists, a profession considered illegal in South Korea. Based on in-depth interviews with 10 Korean tattooists, it explores how they navigate legal and cultural challenges, developing their skills and identities through practice. The process of professional specialization among institutionally marginalized tattooists manifests itself in an unusual form of professional skill development that inevitably requires the relentless refinement of manual skills. The author introduces the concept of unyielding tenacity, which refers to the tattooists’ attitude of persistent practice in the face of harsh conditions created by social constraints. Repetitive practice immerses them in their actions, helping them understand their work, address shortcomings, and question the injustice of the social constraints they face. This points out that before tattooists can adopt the strategy of gaining occupational legitimacy through the artification of their work, a prerequisite is the repetitive performance of their craft.