In the business world, we often come across the term controlling, which is why controlling seems very familiar to all of us, and we are sure that we know what it represents. However, understanding of controlling is very different or often very limiting, and the term controlling often means only some kind of control. Regardless of the fact that controlling is a term that can be written about a lot and in various directions due to its presence in every part of the business, the aim of this thesis is to bring its role and significance in business in at least a little more detail. The most important facts related to controlling are presented, from its appearance in the world and its historical significance to its contemporary role in business. In order to understand the presence of controlling in all business segments, the concepts of controlling, levels or types of controlling and the connection with other subsystems of management are described, especially the importance of controlling in financial management. In the practical part of this work, the importance and role of controlling is shown on the concrete example of a company. Regardless of the fact that the mentioned company does not have an independent controlling department and controlling is applied only in key business segments, the significance of its limited application is of great, even crucial importance, and the aim of this work is to show exactly that.