  We adopt a fully gauge-invariant effective-field-theory approach for
parametrizing top-quark flavor-changing-neutral-current interactions. It allows
for a global interpretation of experimental constraints (or measurements) and
the systematic treatment of higher-order quantum corrections. We discuss some
recent results obtained at next-to-leading-order accuracy in QCD and perform,
at that order, a first global analysis of a subset of the available
experimental limits in terms of effective operator coefficients. We encourage
experimental collaborations to adopt this approach and extend the analysis by
using all information they have prime access to.
