Introduction: Finding an optimal model for the development and functioning of the health care system is an important aspect for most economically developed countries. The aim of this article is to comprehensively study the problems of functioning of complementary (alternative) medicine, to identify the main tendencies of its development in some foreign countries and specific features of its application in Ukraine. Materials and methods: During the research the authors have used theoretical methods (analysis, synthesis, generalization, systematization, etc.) and empirical methods (observation, classification, etc.) of scientific research. Review: The conducted study provides grounds for arguing that complementary (alternative) medicine in various forms exists in most countries of the world and is promoted by the World Health Organization (hereafter – WHO). However, the legal regulation of complementary medicine and its interaction with the traditional medicine are significantly different. It has been established that a significant part of patients use alternative methods of treatment, neglecting the information interaction with the attending physician. The authors have revealed the shortcomings of permitting procedures concerning the activity of healers, the result of which there are many fraud cases in this sphere. Conclusions: The authors have proved the necessity of improving the legislative base for the regulation of complementary medicine, integration of alternative methods into official medicine, improvement of the system of professional training of physicians, determination of the volume of usefulness and benefits of medical aid by alternative methods, expansion of international cooperation and exchange of experience with foreign specialists practicing the use of complementary medicine.