Competence is one of the most commonly used words in nursing internationally, yet is a nebulous concept defined in diverse ways by different healthcare practitioners. The slippery nature of the concept often exists purely in the eye of the beholder however, the universal principles are deeply rooted in the measurement of the Registered Nurse's (RN) ability to perform effectively. Competence is a simpler thing to define when recognising where it does not exist in the form of incompetence. The aim of this paper is to present finding from a concept analysis that explored various facets of competence, particularly how it has been interpreted, applied and transformed over the years within nurse education in the United Kingdom. The analysis utilised a systematic review of contemporary evidence base based on theory construction by Walker and Avant (2005), a primary concern being to understand the underpinning conceptual principles that define the concept of competence and competency development and how these may be used to inform our understandings. The analysis identified how influential academics and professional bodies have attempted to provide definitions and concluded that it may be the existence of so many of these definitions, which has compounded the conundrum of what competence really is.