This volume contains two reviews. The first, "Co-operative Effects in Plasmas" by the late B.B. Kadomtsev is based on the second edition of the author's book in Russian which originated from his written lectures for students of the Moscow Institute of Physics and Technology. Kadomtsev intended to publish the book in English and even initiated the translation himself. The book represents a review of the typical plasma co-operative phenomena that determine the behaviour of laboratory and astrophysical plasmas. The first three sections of the review deal with linear and nonlinear phenomena in fluids without a magnetic field. An additional subsection "Solitons" has been added to the third section. The next two sections address regular nonlinear phenomena in a plasma in a magnetic field. The second review by S.V. Bulanov et al is connected with the contents of the first. The physics of the laser-plasma interaction including such nonlinear processes as wave breaking, the acceleration of charged particles, electromagnetic wave self-focusing, the relativistic soliton and vortex generation, are considered analytically and illustrated using computer simulations.