The workshop is intended to bring together experimentalists, theorists, and phenomenologists focusing on the physics of LHC, ILC and future colliders. We want to trigger discussions and promote the development of the Monte Carlo Event Generator WHIZARD and its interplay with other tools for high-energy physics. Key topics of the workshop will cover all aspects of Monte Carlo event generation. This includes both SM and BSM physics at colliders: beam properties, matrix elements, models and effective theories. QCD, QED and weak radiation, jets, matching and merging, and higher orders. User interface, computing and performance.