The right to self-determination, including the decision on treatment, is affirmed in modern societies. Therefore, the fundamental condition of legal procedures is informed consent of a patient or an authorised person. However, to make the consent legally effective, some conditions have to be met; of these, the provision of comprehensive medical information is of the utmost importance. Thus, a patient is entitled to necessary information provided by a physician. The correlate of this right is the obligation to disclose information which must be fulfilled by a medical practitioner. The aim of this review is to examine this obligation in terms of determining the range of subjects authorised to provide information, the scope of subject information or a set of data, and the manner and time in which it should be given. Moreover, this article discusses regulations which permit limitations of information disclosure, i.e. the patient's entitlement to renounce the right to information, and therapeutic privilege. The disquisition regards achievements of legal doctrine and judicature, from the angle of which all the legal solutions and doubts arising are presented.