A study is made of the transport of a high-current relativistic electron beam over large distances in a gas, in gas and plasma localized channels, and along fine wires in the presence of a continuous transverse magnetic field. The influence of collective fields generated by the beam and of the beam interaction with the plasma channel formed by low-energy electrons is noted in the dispersion of an electron beam in a neutral gas. With reference to the beam transfer in the plasma channel (the diameter of which is significantly greater than the beam diameter), the trajectory in the transverse magnetic field is found to be within plasma channel limits close to the Larmor radius. The effectiveness of the high-current relativistic electron beam is found to be defined by electrostatic and magnetic beam neutralization.