Joint unconventional warfare is the inter-agency, or international implementation of an unconventional warfare strategy, comprising elements of asymmetric warfare, irregular warfare, urban warfare and various forms of psychological operations deployed by non-traditional means.
Joint unconventional warfare would fall under the COIN theory of military operations, generally used in Counter-insurgency operations. The form of military activity has come very much into popular usage under the aegis of General David Petraeus and the former General General Stanley McCrystal.