  We establish a new integral equation for the probability density of the
exponential functional of a L\'evy process and provide a three-term
(Wiener-Hopf type) factorisation of its law. We explain how these results
complement the techniques used in the study of exponential functionals and, in
some cases, provide quick proofs of known results and derive new ones. We
explain how the factors appearing in the three-term factorisation determine the
local and asymptotic behaviour of the law of the exponential functional. We
describe the behaviour of the tail distribution at infinity and of the
distribution at zero under some mild assumptions.
