This study employed qualitative data collection and analysis methods to investigate the influence of English as a foreign language teacher education programme on Korean teachers' classroom teaching practices. Six in-service secondary-school teachers participated in semi-structured interviews. Thematic analysis was applied to the data collected from these interviews. Findings from the analysis included that: a) most of the teachers were dissatisfied with the largely theory-oriented pre-service teacher education programmes that they attended; b) a major source of influence on their teaching was their experience of in-service teacher training programmes with practical curricula; c) observation of other fellow teachers' teaching had the strongest impact upon the teachers' teaching practices; and d) the teachers' low English proficiency and the washback effect of the Korea Scholastic Aptitude Test hindered the maintenance of the changes brought about by in-service teacher education programmes. This study ends with a discussion of the implications of these findings.