The generation of ultra high pressure by laser beams is reviewed in the context of laser driven inertial confinement fusion. Central pressures of 200 GBar are required in an imploded pellet and are achieved by the amplification of the laser generated pressure in the implosion. The theory of laser driven ablation predicts greater efficiency with shorter laser wavelength but with the penalty of greater susceptibility to laser beam non-uniformity. A variety of experimental measurements of laser ablation is described and their results are in good agreement with applicable theories. Factors determining the overall implosion symmetry and pressure multiplication are discussed briefly.