  We review recent results in the study of regular four dimensional BPS black
holes in toroidally compactified type II (or M) theory. We discuss the
generating solution for this kind of black holes, its microscopic
description(s), and compute the corresponding microscopic entropy. These
achievements, which provide a description of the fundamental degrees of freedom
accounting for the entropy of any regular BPS black hole in the theory under
consideration, are inscribed within a research project aimed to the study of
the microscopic properties of this kind of solutions in relation to U--duality
invariants computed on the corresponding macroscopic (supergravity)
description.
