A relativistic description of pian-nucleon scattering based on the four-dim
ensional Bethe-Salpeter equation is presented. The kernel of the equation c
onsists of s- and u-channel nucleon and Delta(1232) pole diagrams, as well
as rho and sigma exchange in the t channel. The Bethe-Salpeter equation is
solved by means of a Wick rotation, and good fits are obtained to the s- an
d p-wave pi N phase shifts up to 360 MeV pion laboratory energy. The coupli
ng constants determined by the fits are consistent with the commonly accept
ed values in the literature. [S0556-2813(99)05008-6].