Abstract
Top-antitop quark pairs belong to the most abundantly produced and precisely measurable heavy-particle signatures at hadron colliders and allow for crucial tests of the standard model and new physics searches. Here we report on the calculation of the next-to-leading order (NLO) QCD corrections to hadronic W+W-b&bmacr; production, which provides a complete NLO description of the production of top-antitop pairs and their subsequent decay into W bosons and bottom quarks, including interferences, off-shell effects, and nonresonant backgrounds. Numerical predictions for the Tevatron and the LHC are presented.