  Pion photoproduction off the nucleon close to threshold is studied in
covariant baryon chiral perturbation theory at O($p^3$) in the
extended-on-mass-shell scheme, with the explicit inclusion of the
$\Delta(1232)$ resonance using the $\delta$ counting. The theory is compared to
the available data of cross sections and polarization observables for all the
charge channels. Most of the necessary low energy constants are well known from
the analysis of other processes and the comparison with data strongly
constrains some of the still unknown ones. The $\Delta(1232)$ contribution is
significant in improving the agreement with data, even at the low energies
considered.
