Traditionally the surgical and technical competence of Residents has been assessed inadequately and has received little attention among the core competencies defined by the Royal College of Physicians and Surgeons of Canada\'s CanMEDS programme and the Accreditation Council for Graduate Medical Education (ACGME). With the development of novel and advanced surgical techniques with different learning curves, time pressure in busy operating rooms, and increasing complexity of cases at university hospitals, acquiring technical skills for Residents has become more challenging. Over the last two decades, methods have been developed to assess technical competence objectively. In this paper we describe use of an Objective Structured Assessment of Technical Skills (OSATS) for total knee replacement (TKR).