This study examines the extent to which lecturers demonstrate effective teaching behaviour. The results of 203 observations reveal substantial differences in detected teaching behaviour. Lecturers mostly demonstrated teaching behaviour in the domains classroom climate, efficient organisation, and instruction. Teaching behaviour relating to the domains activating teaching and teaching learning strategies was observed less frequently, with almost no evidence of behaviour associated with the domain differentiation. The quality of teaching in small classes was slightly higher than that in large classes. These findings can help tailor professional learning activities to lecturers' professional development needs.