This article affirms the existence and need for nursing knowledge and supports this claim with definitions and points of reference from other disciplines. It briefly summarizes the evolution of nursing knowledge, mostly from a North American perspective, and it examines its presence in scholarly work on nursing so as to highlight some conclusions and briefly present two explanations related to the use and development of nursing knowledge by the nursing community. In conclusion, the necessity of learning, analyzing, testing, and using nursing knowledge is reiterated.