Developments in perturbative QCD: challenges from collider physics

The search for new phenomena at hadron colliders requires a good understanding of QCD processes. The analysis of multi-jet signatures in the top quark search at the Tevatron is one example, forward jet-tagging and rapidity gap techniques in the analysis of weak boson scattering events at the LHC will be another important application. These topics are discussed in the context of multi-parton/multi-jet QCD processes. Also described are some of the calculational tools, like amplitude techniques and automatic code generation for tree level processes.