This thesis contains a summary about the voltage dip within the thematics of the power quality. The summary is based mostly on the available foreign and native literature, on the notes and lectures from the university, measurement results and on the concerning standards for the power quality. I tried to create some general sections in the thesis which seemed to be logic for me. The first section is about the IEC 61000-4-11 standard, I tried to highlight the most important parts of it. This is followed by the definition and the measurement method of the voltage dip. At the end of this section I briefly wrote about the measuring instruments. The next three chapters are about the voltage dip, its formation, spreading and evaluation. The voltage dip is mostly caused by a short circuit, so that is the main topic in the formation section. In the spreading section I wrote about the high and medium-voltage network, then about the phase-angle jump. At the end I described the loss and the voltage dip caused by a phase-to-ground fault in the transition from the medium to the low-voltage network. This section also contains the determination of the direction of the voltage dip, the caused problems because of the voltage dip and the reduction of these problems. The next chapter is about the mini power plants, its behavior. This is followed by a bigger section which describes the evaluation of the measurements, where the emphasis is on the sensitivity curves. At the end of this section I wrote about the statistics of the drop-out of low-voltage equipments. The end of the thesis contains the development strategies and standardizations in the network todays and in the future.