Background: Medical education involves learning and practice in a variety of classroom and clinical contexts. Clinical skills, including patient communication and history taking, are usually learnt initially in a classroom context, often using role-play with peers or simulated patients before applying skills with real patients in clinical rotations. Yet, evidence is lacking to show how students apply their communication knowledge to practice in real and simulated settings. This study sought to investigate the alignment between students’ perceptions of good communication in medical history taking and their behaviour in simulated interviews. Methods: 20 medical students at varying educational levels engaged in qualitative interviews that focused on information gathering in medical communication. They were asked about how they elicit information from patients and what qualities and strategies make a good medical history-taker. Interviews were coded thematically to identify students’ knowledge of effective questioning. Next, students engaged in a standardised role play assessment, which was coded to provide measures of the behaviors they used in practice. Coding was based on the Calgary-Cambridge guides to the medical interview and accepted definitions of question and utterance types. Findings: Students had good knowledge and practice of sociomotivational behaviors like being empathic and non-judgmental. In contrast, there was a gap between knowledge and practice for effective questioning. Three quarters of the questions asked by students in the role-play were of the most constrained type, despite over half discussing the importance of open questions in their interview. Discussion: The misalignment between students’ knowledge of good communication and their behaviour in simulation warrants further investigation. Further work is needed to develop training methodologies that target this gap. For example, the practice of having students objectively evaluate (i.e. code) their own interviews is discussed as one possible way to help students assess their own practice.