In matter fast ions deposit their kinetic energy mainly via the nuclear energy loss and via the electronic energy loss. The former denotes the process of transfer of kinetic energy to the material atoms as a whole whereas the latter leads to excited and/or ionized target atoms. With the advent of the megavolt implanters in science and technology the component of the electronic energy loss grows in its importance. Reviewing recent experiments in the ion energy range of 100 to 1000 MeV it is shown that in all amorphous materials (polymer glasses, dielectric, metallic glasses) atomic rearrangements are released by electronic excitations. In the low-fluence region particle track formation is the most important process whereas in the high-fluence region ion-beam-induced plastic deformation causes macroscopically visible specimen deformations. Finally, it is shown that the latter effects are also of importance in the field of implantation of ions of several MeV.