The importance of team communication, or more specifically speaking up, for safeguarding quality of patient care is increasingly being endorsed in research findings. However, little is known about speaking up of clinical teachers in postgraduate medical training. In order to determine how clinical teachers demonstrate speaking up in formal teaching team meetings and what factors influence this, the authors carried out an exploratory study based on ethnographic principles. The authors selected 12 teaching teams and observed, audio recorded and analysed the data. Subsequently, during an interview, the program directors reflected on speaking up of those clinical teachers present during the meeting. Finally, the authors analysed iteratively all data, using a template analysis, based on Edmondson's behaviours of speaking up. The study was conducted from October 2013 to July 2014 and ten teams participated. During the teaching team meetings, the clinical teachers exhibited most of the behaviours of speaking up. "Sharing information" strongly resembles providing information and "talking about mistakes" occurs in a general sense and without commitment of improvement activities. "Asking questions" was often displayed by closed questions and at times several questions simultaneously. The authors identified factors that influence speaking up by clinical teachers: relational, cultural, and professional. The clinical teachers exhibit speaking up, but there is only limited awareness to discuss problems or mistakes and the discussion centred mainly on the question of blame. It is important to take into account the factors that influence speaking up, in order to stimulate open communication during the teaching team meetings.