We evaluate in the one-loop approximation of chiral perturbation theory all one- and two-pion exchange contributions to elastic NN-scattering. We find that the Delta(1232)-excitation produces the correct amount of scalar isoscalar attraction as needed in the peripheral partial waves with $L>=3$. Thus no explicit sigma meson is needed. The two-loop diagrams of correlated two-pion produce negligilby small repulsive corrections. Vector meson exchamge becomes important in the F-waves above 150 MeV.