  The production of a Higgs boson in association with a pair of top-antitop or
bottom-antibottom quarks plays a very important role at both the Tevatron and
the Large Hadron Collider. The theoretical prediction of the corresponding
cross sections has been improved by including the complete next-to-leading
order QCD corrections. After a brief description of the most relevant technical
aspects of the calculation, we review the results obtained for both the
Tevatron and the Large Hadron Collider
