In a multicultural democratic society, the increasing demographic diversity within and across nation-states calls attention to pedagogical knowledge and skills needed to engage students in discussing controversial cultural issues (CCIs). Woven in the intersection of democratic education and multicultural education, this qualitative study sought to unravel the nature and process of teachers' decision-making for their instruction of CCIs by taking a closer look at the experiences of three South Korean elementary teachers. The findings highlight how the teachers' conceptions of certain cultural issues have changed over time with the nation's growing demographic diversity, how the shift in their perspectives has affected their professional judgement for the instruction of such issues, and how the teachers' cultural critical consciousness impacts their professional judgement.