  We investigate the structure of the nucleon resonance N^*(1440) (Roper)
within a coupled-channel meson exchange model for pion-nucleon scattering. The
coupling to pipiN states is realized effectively by the coupling to the sigmaN,
piDelta and rhoN channels. The interaction within and between these channels is
derived from an effective Lagrangian based on a chirally symmetric Lagrangian,
which is supplemented by well known terms for the coupling of the Delta isobar,
the omega meson and the 'sigma', which is the name given here to the strong
correlation of two pions in the scalar-isoscalar channel. In this model the
Roper resonance can be described by meson-baryon dynamics alone; no genuine
N^*(1440) (3 quark) resonance is needed in order to fit piN phase shifts and
inelasticities.
