The aim of this paper is to point to the influence of information support systems for decision making on successful business operations. The company management whishing to do business successfully should act promptly and appropriately in order to achieve and maintain the leading market position. Therefore, companies should bear in mind the fact that successful decision making nowadays is not possible without applying modern information technology, i.e. modern information support systems for decision making. Information technologies in many areas of business activities have strategic position and both existence and development of a company depend on their application. Information technologies enable creating new products and services tailored to customers' needs, therefore creating a competitive advantage for the company on the market. Moreover, they support the decision making process on all levels of a business system (operational, tactic and strategic), enable improved decision making, archiving, creating and sharing of knowledge and responsibilities amnog the employees in the company and in that way contribute to the efficiency of the business. Introducing information technologies into a business system leads to the organizational changes and requires reengineering the existing business processes and contributes to faster and improved decision making as well as to the reduction of costs. Reengineering and information technology application creates new forms of organizations: informational, technological and virtual organizations, i.e. organizations of the future. In order to do business successfully, it is necessary to build and use on the daily basis a system which enables collecting, processing, storing and accessing data whenever and wherever it is required, at the same time providing a reliable support to a manager. The application of inforamtion technologies is of strategic importance to each business because information technologies reduce costs, speed up admnistration, encourage decision making, create competitive advantage, become a strategic weapon, increase productivity and make work more comfortable, successful and efficient.