  Using the collective variables (CV) method the basic relations of statistical
field theory of a multicomponent non-homogeneous fluids are reconsidered. The
corresponding CV action depends on two sets of scalar fields - fields
$\rho_{\alpha}$ connected to the local density fluctuations of the $\alpha$th
species of particles and fields $\omega_{\alpha}$ conjugated to
$\rho_{\alpha}$. The explicit expressions for the CV field correlations and
their relation to the density correlation functions are found. The perturbation
theory is formulated and a mean field level (MF) of the theory is considered in
detail.
