  We discuss the interplay between NLO QCD corrections and anomalous couplings
in Higgs boson pair production via gluon fusion, within the framework of a
non-linearly realised Effective Field Theory, described by the electroweak
chiral Lagrangian. We study how the NLO corrections with full top quark mass
dependence affect the total cross sections as well as distributions in the
Higgs boson pair invariant mass. For a large part of the parameter space,
significant and non-homogeneous K-factors arise.
