  We consider the duality between the four-dimensional S-matrix of planar
maximally supersymmetric Yang-Mills theory and the expectation value of
polygonal shaped Wilson loops in the same theory. We extend the duality to
amplitudes with arbitrary helicity states by introducing a suitable
supersymmetric extension of the Wilson loop. We show that this object is
determined by a host of recursion relations, which are valid at tree level and
at loop level for a certain "loop integrand" defined within the Lagrangian
insertion procedure. These recursion relations reproduce the BCFW ones obeyed
by tree-level scattering amplitudes, as well as their extension to loop
integrands which appeared recently in the literature, establishing the duality
to all orders in perturbation theory. Finally, we propose that a certain set of
finite correlation functions can be used to compute all first derivatives of
the logarithm of MHV amplitudes.
