  I discuss the problem of formulating the baryon chiral perturbation theory
($\chi$PT) in the presence of a light resonance, such as the $\Delta(1232)$,
the lightest nucleon resonance. It is shown how to extend the power counting of
$\chi$PT to correctly account for the resonant contributions. Recent
applications of the resulting chiral effective-field theory to the description
of pion production reactions in $\Delta$-resonance region are briefly reviewed.
