Even though there is a wide range of regional resource synergy projects throughout the world, categorisation of synergistic connections and their related benefits is not obvious. A detailed study of existing industrial regions has resulted in a proposed classification system for regional synergies based on their economic and environmental benefits. Depending on their type and effectiveness, synergies are classified into nine groups: from business synergies (strong economic and additional ecological benefits), to better waste neutralisation and disposal (economic cost and average ecological benefits), and to symbiotic synergies (strong economic and ecological benefits). The classification system forms part of a new Regional Resource Synergies Framework. Its application is illustrated here with well-known European examples (Kalundborg, Forth Valley), as well as examples from Australian (Gladstone) and Russian (Berezniki) industrial regions. (C) 2011 Elsevier Ltd. All rights reserved.