Non-maleficence represents one of the basic ethical principles that health care providers should be guided by during service delivery. Establishment of patient safety is nowadays recognized as an issue of global concern in health care and a critical component of quality management. The aim of this paper is to provide a literature review of the patient safety and medication errors concept, with special attention given to defining the most significant terms, analyzing the causal factors and reviewing their classification. Raising awareness about the importance of patient safety has resulted in an increase in the number of medication error studies over the last decade. The traditional approach which makes health workers responsible for reduction of incidents is replaced by the modern concept which implies the involvement of all stakeholders at all levels of the system. In developed countries, the application of prospective risk management models for specific health care processes has already started. However, all these studies are mainly carried out at the secondary and tertiary levels of health care, while they are almost non-existent at the primary level. In the Republic of Serbia, a Rulebook on indicators of the quality of health care has been recently adopted, but a trend of significant lack of data regarding patient safety can be noticed due to inadequate reporting. It is necessary to continue with the homogenization of terminology and to increase the number of analyses of causal factors with the aim of prospective risk identification, particularly in developing countries such as the Republic of Serbia.