Professionalism is a broad competency needed by dentists to act effectively and efficiently and is seen as a central part of both undergraduate and postgraduate curricula. Assessment is vital in education to assess progress and direct future learning. It is also an essential part of good professional regulation, which depends upon high quality assessment to maintain credibility. Educators must produce clear expectations that students can strive for. Thus dental educators are required to understand precisely what is meant by “professionalism” in relation to dentistry in order to both teach and assess it. The aim of this paper is to explain the importance of professionalism, explore its features and its assessment as described in the literature. The paper concludes that without a validated definition of this construct, assessment of professionalism within dental education will be compromised.