Aims and method To investigate medical students' performance at and perceptions of the mental state examination (MSE) at a medical school with a modern integrated curriculum. We undertook an evaluative case study comprising a survey and analysis of performance data. The study is presented in two parts: part 1 discusses the students' perceptions of the MSE and the teaching, learning and practising of it. Results Most students in the study group considered the MSE an important examination in medicine. Other perceptions grouped in themes are presented. Unsurprisingly, most students found psychiatric attachments the most useful part of the course for learning about the MSE. About a half of students had witnessed an MSE being undertaken in clinical practice. Clinical implications Although students appear to recognise the importance of this examination in medicine, the teaching and learning of it possibly needs greater emphasis in the undergraduate curriculum, and teaching and learning opportunities improved throughout the course.