An unified description of the transport theory for charged particles i
ncluding electrons, ions and atoms has been formulated and is presente
d. The main content of the paper includes: the Boltzmann equation and
iu different approximations, the theory of electron slowing down spect
ra, multiple scattering theory, the theory of deep penetration and the
theory of secondary particle emission. The scaling properties of the
transport of charged particles are also presented. Although some discu
ssion of stochastic (Monte Carlo) methods is included, the main focus
of this review is on analytical approaches. Finally, some important un
solved problems in the transport theory for charged particles are disc
ussed.