INTRODUCTION: In this article an analysis is made of existing legal provisions and policies regarding medical confidentiality and the use of medical information on pilots, for the reporting of unfit pilots and for accident and incident investigation. An overview is given of the applicable international, European and several national legal frameworks in relation to this question. The applicable national legislation and relating policies of the Netherlands, the U.S., and Canada are compared on this subject. These three States (countries) are selected because of the differences between them in legal provisions when it comes to medical confidentiality of pilots’ health information. The article will conclude with tools derived from this analysis, which can be used to find a balance between medical confidentiality vs. aviation safety.Schuite JM. Aviation safety vs. medical confidentiality: disclosure of health information for accident prevention and investigation. Aerosp Med Hum Perform. 2019; 90(10):872–881.