The diploma thesis „Assessment of a Company's Information System and Proposal for Modifications” deals with the issue of security and efficiency of the information system. The thesis is divided into three parts. The first theoretical part explains the basic concepts that are subsequently used in the thesis. The second part contains analytical starting points and introduction of the company, its analysis and analysis of the information system. This information is the basis for the last proposal part, where its content is to increase the security of the company's information system. Part of the proposal also includes an economic assessment, where benefits and costs are described. The work is elaborated in order to achieve the assigned goal of...