||The main objective of this thesis is to examine day surgery from an economic point of view and to show that in comparison with inpatient surgery it is a more cost-effective way of provision of health care. The definition of day surgery, its possible scope of use and its positive and negative features are presented in the first part of the thesis. The next part is dedicated to the history of day surgery and its development in different countries of the world throughout the 20th century and at the beginning of the 21st century. Moreover, the relation between the use of day surgery and the average length of stay is examined as well as the possible causes of variations in the use of day surgery. Economic advantages of day surgery are discussed on the basis of several studies which compare the costs of day and inpatient surgery for different types of procedures. In the last part of the thesis we try to estimate the social costs of day and inpatient surgery in the Czech Republic. Three procedures are selected and the opportunity costs resulting from not treating the patient as a day case are calculated for each of them.