The information system is the main subject of consideration in this paper. Information and data as well as their significance in the business information system will be presented. The functioning of the information system is based on the collected data and information as an important resource in the information system. The quality, timeliness and accuracy of the information gathered and its further handling within an organization result in the upgrading and improvement of the existing business and give support for the necessary management and decision making. The phases of an accounting information system that is a part of the overall information system and is responsible for carrying out accounting tasks will be elaborated. By elaborating the above mentioned phases, we will come to the conclusion of when and why it is necessary to introduce a new information system, the advantages and disadvantages of its introduction, the possible difficulties that may arise between individual phases as well as the benefits of introducing a new information system. The practical part will describe in detail the operation and functioning of courts in the Republic of Croatia and their information system - networking between courts for the purposes of data exchange and monitoring of statistics of types of decisions etc., the use of various records and applications up to the use of modern information technology such as the Internet and electronic processing and the exchange of information and data. All of the above will illustrate the facts that have contributed to faster, more efficient and easier business, data collection, and their transformation into information which is the main product of the information system for delivering solutions and making quality business decisions.