We give a pedagogical account of recent progress concerning the computation of scattering amplitudes of planar maximally supersymmetric Yang-Mills in four dimensions at strong coupling by means of the AdS/CFT correspondence. Two important ingredients of the computation are the presence of a 'dual' conformal symmetry and the equivalence between the scattering amplitude and a particular kind of light-like cusped Wilson loops. We discuss recent progress extending these two features to all values of the coupling constant. © 2009 IOP Publishing Ltd.