The majority of the "memorable" results of relativistic quantum theory
were obtained within the framework of the local quantum field approach.
The explanation of the basic principles of the local theory and its
mathematical structure has left its mark on all modern activity in this
area. Originally, the axiomatic approach arose from attempts to give a
mathematical meaning to the quantum field theory of strong interactions
(of Yukawa type). The fields in such a theory are realized by operators
in Hilbert space with a positive Poincare-invariant scalar product. This
"classical" part of the axiomatic approach attained its modern form as
far back as the sixties. * It has retained its importance even to this
day, in spite of the fact that nowadays the main prospects for the
description of the electro-weak and strong interactions are in
connection with the theory of gauge fields. In fact, from the point of
view of the quark model, the theory of strong interactions of Wightman
type was obtained by restricting attention to just the "physical" local
operators (such as hadronic fields consisting of ''fundamental'' quark
fields) acting in a Hilbert space of physical states. In principle,
there are enough such "physical" fields for a description of hadronic
physics, although this means that one must reject the traditional local
Lagrangian formalism. (The connection is restored in the approximation
of low-energy "phe- nomenological" Lagrangians.