The survey presented shows that despite the intensive study of the physical problems of ion implantation in GaAs, there is still a number of questions to investigate. Among them are: The role of anomalous diffusion and channeling in the formation of concentration profiles, the anomalous diffusion mechanism, the influence of radiation defects and residual impurities as well as the form of the coating, the interaction between impurities and defects under ion implantation, and the identification of radiation defects, A further study of the above-mentioned questions will permit extension of the application of the ion implantation method to obtain GaAs semiconductor instruments and realization of still unused possibilities of this powerful method of modern semiconductor technology.