This case study investigates Carolyn, an effective volunteer ESL and literacy instructor of adult African refugees, in order to understand both what it means to be a qualified instructor, and also how community-based volunteer instructors may become more qualified. The study's findings suggest that Carolyn's qualifications are a combination of personal dispositions, such as cultural sensitivity, and professional behaviors, including self-education, seeking mentoring and outside expertise, and purposeful reflection on her teaching. Several implications for supporting community-based volunteer literacy and ESL instructors emerge from these findings.