2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/227008The search for signals of new physics at the forthcoming LHC experiments involves the analysis of final states characterised by a high number of hadronic jets or identified particles. Precise theoretical predictions for these processes require the computation of scattering amplitudes with a large number of external particles and beyond leading order in perturbation theory. The complexity of a calculation grows with the number of internal loops as well as with the number of external legs. Automatisation of at least next-to-leading order calculations for LHC processes is therefore a timely task. I will discuss various approaches.43 pages, plenary talk given at the ACAT 07 conference, Amsterdam, 2007; v2: references addedHigh Energy Physics - Phenomenologytext