The interpretive survey study reported in this paper aimed to understand in-service English language teachers' views of in-service teacher education (INSET) programmes offered by the Ministry of National Education in Turkey. Data were collected from 2476 in-service teachers through an online questionnaire that contained closed- and open-ended items. Central tendencies were calculated and content analysis was used to analyse quantitative and qualitative data, respectively. According to the findings, participants disagreed about the effectiveness of these programmes. They reported that these programmes were effective in terms of promoting their professional development, personal development, and cooperation between colleagues; however, issues emerged regarding the weaknesses of these programmes in six main areas: the limited number of programmes on offer, the lack of qualified trainers, insufficient practical focus, poor lecturing, inconvenient time and place, and the perfunctory nature of the INSET offered. In the light of these findings, implications are generated to contribute to the improvement of the effectiveness of future in-service teacher education programmes.