The presented analysis leads to a conceptual discussion of solidarity and empirical findings concerning solidarity behavior in disasters. Selected academic articles are analyzed and contrasted with the EU's structural solutions and functional experiences in the field of disaster solidarity. In the liminal period of a disaster, emerging actors spontaneously, collectively and altruistically provide assistance to victims. They act based on shared values ​​and norms and ignore pre-disaster normative social differences and behaviors. Ethical dimensions and emotions are also crucial for solidarity behavior. This solidarity is then reinforced by local, national and in some more serious cases even international actors. One of these is the Union Civil Protection Mechanism (UCPM), which provides regional and global assistance. The solidarity of the UCPM is mechanical, organic and based on a case-specific mix of generosity, morality, rationality, reciprocity, identification, connectedness and interdependence. The UCPM has functional goals and political motives.