  The present review is devoted to a Chiral Cosmological Model as the
self-gravitating nonlinear sigma model with the potential of (self)interactions
employed in cosmology. The chiral cosmological model has successive
applications in descriptions of the inflationary epoch of the Universe
evolution; the present accelerated expansion of the Universe also can be
described by the chiral fields multiplet as the dark energy in wide sense.
  To be more illustrative we are often addressed to the two-component chiral
cosmological model. Namely, the two-component chiral cosmological model
describing the phantom field with interaction to a canonical scalar field is
analyzed in details. New generalized model of quintom character is proposed and
exact solutions are founded out.
  In the review we represented the perturbation theory for chiral cosmological
model with the aim to describe the structure formation using the progress
achieved in the inflation theory. It was shown that cosmological perturbations
from chiral fields can be decomposed for inflaton and the dark sector
perturbations. The two-component model is investigated in details, the general
solution for shortwave approximation is obtained and analyzed for power law
Universe expansion.
  New issue for understanding the features of Universe evolution is proposed by
consideration of the dark sector fields on the inflaton background. The results
are illustrated for the solutions in the long-wave approximation.
