  Different approaches to axionatic field theory are investigated. The main
notions of semiclassical theory are the following: semiclassical states,
Poincare transformations, semiclassical action form, semiclassical gauge
equivalence and semiclassical field. If the manifestly covariant approach is
used, the notion of semiclassical state is related to Schwinger sourse, while
the semicalssical action is presented via the R-function of Lehmann, Symanzik
and Zimmermann. Semiclassical perturbation theory is constructed. Its relation
with the S-matrix theory is investigated. Semiclassical electrodynamics and
non-Abelian gauge theories are studied, making us of the Gupta-Bleuler and BRST
approaches.
