MCnet is a collaboration between the developers of the major collision-event modelling tools used at the Large Hadron Collider (LHC) and beyond. These codes are so-called “MC event generators”, theoretical physics packages that evaluate and sample from quantum mechanical distributions to create simulated particle collisions. MC generators are an essential component of both modern particle physics experiments and theory, and provide a crucial bridge between those two communities. MCnet projects include both event generators themselves, and tools that connect them to both experiment and theory.