Description Considerable attention is paid to the phenomena that are specific to quasi-2D and Quasi-ID conductive structures and have no analogues both in ordinary metals and in truly 2D or OD conducting systems. Angular magnetoresistance oscillations, de Haas-van Alphen and Shubnikov-de Hass phenomena, and high-frequency resonances, including those arising due to the movement of electron on open trajectories, are discussed. The resonant angular oscillations of high-frequency conductivity and weakly damped electromagnetic waves in quasi-2D organic conductors under strong spatial dispersion are considered. We review high frequency collective processes in highly anisotropic conducting systems in the presence of an external magnetic field taking into account of the Fermi-liquid interaction. The specific of the quasi-two-dimensional electron energy spectrum and of the Fermi-liquid interaction in layered conductors leads to occurrence of weakly-damping eigen oscillations of the electron and spin densities which are absent in a quasi-isotropic metal