Abstract
The experimental tools, that is frequency-dependent conductivity and quasi-elastic neutron scattering, are briefly outlined. Spectra are then presented, and the dynamic information is read from them. As a result, the elementary steps of translational motion of ions in solids can be described on atomic scales of space and time. Emphasis is put on clear-cut examples. Dispersive radio and microwave conductivity spectra are indicative of marked deviations from random jump diffusion. Spectra of this kind are typically found in structurally disordered solid electrolytes. A self-consistent explanation is provided by the process of jump relaxation.