Evidence-based dentistry is a new, worldwide trend in the field of clinical dentistry. Despite this fact, it has been neglected in Korean dental community. Thus, its basic concepts and the 5-step procedures are introduced and described in this 2-part series report. Evidence-based dentistry is a method of clinical practice where the clinicians use the best available research evidence for their own clinical decision making. By using this method, the clinical outcomes can be improved and the clinicians themselves can have the ability to keep watch over their daily practices. To clinically apply the principles of evidence-based dentistry, dental practitioners have to formulate a clear question, find the best available research evidence efficiently, critically appraise the evidence systematically, apply the results of the evidence to their practice, and evaluate the clinical outcomes comprehensively. In building a clinical question, it is essential to categorize questions according to their types followed by their organization using the key elements. Then, literature search must be done. There are many web sites for searching evidence, but PubMed is considered to be the leading site. To efficiently search the literature, search term must be selected appropriately and the search results should be limited.