In medical training and practice, our professional attributes, attitudes, perceptions, character traits and identities are fundamentally shaped by our lived experiences and observations in clinical and para-clinical settings instead of being inculcated through formal curriculum or classroom teaching. For instance, clinical acumen, communication skills and bedside manners are learnt through role modelling and experiential learning in the course of clinical rotations. Likewise, one's attitudes, professional behaviours and inclinations are often also influenced by direct/indirect observations of the actions of others in the medical fraternity in various clinical and non-clinical settings. This is also what is often termed as the 'hidden curriculum' of medicine. In this article, we sought to provide a practical conceptualisation of the hidden curriculum in medical training, which we describe as lived experiences and personal observations of medical trainees and residents in clinical and para-clinical spaces, which shape their perceptions of the medical profession (vocational identity and purpose), patients (patient-physician relationship) and colleagues (intra- and inter-professional relationships), with downstream implications on physician well-being and clinical decision-making. Although this idea of a 'hidden curriculum' has conventionally carried predominantly negative connotations in medical literature, we suggest that it is an inevitable part of medical education and practice, which, through deliberate regulation, can potentially be shaped to create more positive and meaningful effects in the professional development of medical trainees.