The diploma thesis surveys the most important problematic fields of the patient safety issue; particularly in the context of drug administration. In the general part there are described the risks associated with LASA medications, using of concentrated electrolyte solutions, incorrect patient identification and wrong communication. Reported clinical cases of medication errors that occurred in connection with the triggers mentioned above are demonstrated and there are listed recommendations aimed at preventing the adverse events and assuring safe care. The closing part of the thesis describes and compares how the Antwerp University Hospital and three teaching hospitals in Prague ensure the safety of drug administration. The thesis manifests a noticeably more elaborate system of education and promotion of the patient safety issues both among the staff and among the patients and their families in the Antwerp University Hospital. Also the technical assuring of the right medication (barcode scanners, automated dispensing devices in certain wards etc.) was in the Belgian hospital on higher level comparing to the average of the followed Czech hospitals.