'High Energy Jets' provides an approximation to the all-order perturbative calculation of observables in processes with multiple hard jets. I will discuss first the basics of the framework, and recent comparisons to data from both the LHC and the Tevatron. Secondly, I will discuss the possiblities for measuring e.g.~the $CP$-properties of the Higgs boson couplings provided by multi-jet observables, and the r\^ole of High Energy Jets in such analyses.
The Particle Physics Theory seminar is a weekly series of talks reflecting the diverse interests of the group. Topics include analytic and numerical calculations based on the Standard Model of elementary particle physics, theories exploring new physics, as well as more formal developments in gauge theories and gravity..