Earthquake swarms occur in various geological units. They have been studied from various aspects; however, the factual mechanisms of their origination and development have still remained undisclosed. The principal objective of the proposed project is to reveal the causes leading to the seismic energy release in the form of earthquake swarms instead of ordinary single events or mainshock-aftershock sequences. In our project, we will investigate the earthquake swarms from three European swarm regions: West Bohemia/Vogtland, South Iceland and French Alps, with the aim to find characteristics dependent and independent on the tectonic environment. On the basis of these analyses we plan to derive at least a simplified model of the preparation, triggering and driving of the earthquake swarms. In such a model, we will involve tectonic stress, crustal fluids pore pressure and Coulomb stress changes. A particular attention will be paid to the role of crustal fluids and magma in the origination and development of the earthquake swarms.