This advanced textbook on fundamental macroscopic plasma physics emphasizes the nonlinear and relativistic effects due to laser-plasma interactions. Experiments with lasers of high intensity helped to discover new quantum effects and the longitudinal components of optical radiation in vacuum, and this in turn led to an extension of basic plasma physics, which is presented here together with its impact on classical topics such asinstabilities, solitons, resonance absorpption, etc. The reader will also find sections on energy problems and nuclear fusion.