  Quark-hadron duality addresses some of the most fundamental issues in strong
interaction physics, in particular the nature of the transition from the
perturbative to non-perturbative regions of QCD. I summarize recent
developments in quark-hadron duality in lepton-hadron scattering, and outline
how duality can be studied at future high-luminosity facilities such as
Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.
