  The possibility of revealing new physics by studying the flavor sector of the
Standard Model strongly depends upon the accuracy that will be achieved in
(near) future lattice QCD calculations and, in particular, on heavy-light
meson's observables. In turn, handling with heavy-light mesons on the lattice
is a challenging problem, because of the presence of two largely separated
energy scales, and at present it is impossible to extract matrix elements
involving B mesons in external states without recurring to some approximation.
In this note I give a fast overview of some of the methods that have been
devised to handle such kind of problems, emphasizing those based on finite
volume techniques, and briefly discuss some recent results obtained by their
application.
