This paper deals with the topic of the IT grounding system in low-voltage networks with the task of presenting the most important features of that system. In low-voltage networks, the main goal of choosing an appropriate grounding system is the safety of consumers who use electrical devices and their protection from electric shock. The IT system is one of the five possible variants of the system prescribed by international standards, in addition to the TN-C, TN-S, TN-C-S and TT system. The most important advantage of the IT grounding system is that it provides the possibility of continuous delivery of electricity even in fault conditions. In the case of the first failure, the current and voltage conditions in the network are within safe values, while in the event of the second failure, the current and voltage levels exceed the permitted limits, which is proven by calculations. For this reason, fast detection, localization and removal of the first fault is required, which is achieved by insulation monitoring devices paired with fault locators. Due to the susceptibility of electrical networks to the occurrence of overvoltages, various causes of their occurrence and ways of protecting the network from them are observed. By observing the advantages and disadvantages of this system, it can be concluded when designing, when to give priority to the IT system, and when to other systems.