  In a landmark paper, D.Y. Kleinbock and G.A. Margulis established the
fundamental Baker-Sprindzuk conjecture on homogeneous Diophantine approximation
on manifolds. Subsequently, there has been dramatic progress in this area of
research. However, the techniques developed to date do not seem to be
applicable to inhomogeneous approximation. Consequently, the theory of
inhomogeneous Diophantine approximation on manifolds remains essentially
non-existent.
  In this paper we develop an approach that enables us to transfer homogeneous
statements to inhomogeneous ones. This is rather surprising as the
inhomogeneous theory contains the homogeneous theory and so is more general. As
a consequence, we establish the inhomogeneous analogue of the Baker-Sprindzuk
conjecture. Furthermore, we prove a complete inhomogeneous version of the
profound theorem of Kleinbock, Lindenstrauss & Weiss on the extremality of
friendly measures. The results obtained in this paper constitute the first step
towards developing a coherent inhomogeneous theory for manifolds in line with
the homogeneous theory.
