Evidence-based nursing is the concept of critically appraising the best evidence from research. It integrates research evidence with clinical expertise into decision making in nursing care for patients. The method is derived from the new paradigm in medicine--evidence-based medicine, developed as a learning method by epidemiologists at the McMaster University in Canada. This article states the necessity of this method for nursing. With the help of a clinical scenario (fall prevention in the elderly) the author explains how to use evidence-based nursing in practice.