  We present a relativistic calculation of pion scattering, pion
photoproduction and Compton scattering on the nucleon in the energy region of
the \Del-resonance (upto 450 MeV photon lab energy), in a unified framework
which obeys the unitarity constraint. It is found that the recent data on the
cross section for nucleon Compton scattering determine accurately the
parameters of the electromagnetic nucleon--\Del\ coupling. The calculated
pion-photoproduction partial-wave amplitudes agree well with the recent Arndt
analysis.
