This work deals with the operation of Data Boxes in relation to public institutions, namely the Czech Social Security Administration. The introduction is devoted to a summary of the historical development of Data Boxes and description of the basic rules for using the Information System of Data Boxes. There is a mention of the role of Data Boxes in the Czech eGovernment and its relationship to the other elements. Finally, there are listed and briefly discussed the basic legislation with the problems related to Data Boxes. The next part deals with analysis of the situation in the Czech Social Security Administration in the sphere of Data Boxes. It describes situation in the delivery of documents before commissioning of Data Boxes and the situ...