Science and technology education has become increasingly important. However, for most teachers, it is challenging to provide this content. Therefore, professional development programmes are used to support teachers in this regard. In this qualitative study, effective characteristics that should be present in such programmes were identified. Moreover, four particular professional development programmes were investigated to see whether they included these characteristics. Eleven review studies and meta-analyses were analysed to identify the effective characteristics of professional development programmes for science and technology education. Five content characteristics were distinguished: focus, activities, collaboration, coherence of content, and duration. In addition, three contextual characteristics were distinguished: coherence with context, individual factors, and organisational factors. The materials from four professional development programmes for science and technology education were collected and analysed and interviews were held with principal investigators who were involved in the design of these programmes and with educators who worked with these programmes. The characteristics duration and coherence with context appeared to be fully addressed in respectively two and one programmes. The other characteristics were incorporated to a limited extent or not at all. Overall, the present study illustrated the apparent challenges in designing professional development programmes.