This brief study presents an overview of the different types of spill-over effects of metropolitan regions on surrounding areas as well as the diverse solutions and governance set-ups designed to manage these effects. It culminates in recommendations to strengthen metropolitan cooperation as well as the possible role of ESI-funds. There are numerous types of interlinkages between urban, intermediate and rural areas which are affected by metropolitan spillovers. These include societal links evident in phenomena such as urban-rural and rural-urban migrations leading to phenomena such as sub-urbanisation, urban sprawl or counter-urbanisation. Such societal links have various origins and are also linked to economic spillovers.
Economic spill-over effects most notably refer to agglomeration advantages as well as exchanges between different types of territories in terms of consumers and trade, where cities act as regional outlet markets. Last but not least, these social and economic activities have environmental spillovers reflected in land take, soil sealing, air pollution, urban heat, water supply, waste and waste water disposal. Diverse governance set ups manage these positive and negative effects and there are different uses of ESI-funds that metropolitan areas can exploit. The study has analysed several cases: Barcelona, Frankfurt, Katowice, Nantes, Rheintal and Stockholm. Common recommendations for all metropolitan areas are as follows: work towards a common perception of challenges and goals as well as build trust, encourage development of a regional identity, adjust the appropriate form of cooperation and find the appropriate cooperation topic as well as take small steps first.