Urban bioregion concept: from theoretical roots to development of an operational framework in the European context David Fanfani Florence University Department of Architecture -DidA Email: david.fanfani@unifi.it Tel: 0552756482 Barbora Duží Institute of Geonics of the Czech Academy of Sciences Department of Environmental Geography Email: barbora.duzi@ugn.cas.cz Abstract In urban planning literature and practice, a growing attention is paid to the possibilities of enhancing the interaction between rural and urban domains and ‘re-embedding' of cities within their surroundings. In this sense, the concept of ‘urban bioregion’ could play a pivotal role for application i n practice through peri-urban integrated policies of the territorial planning. Although the bioregional approach emerged several decades ago, mainly in the North American context, the bioregion concepts need to be further developed in planning domain. It turns out to be especially remarkable in the European peri-urban context where the city-countryside relationship historically underpinned the human settlements form. In this framework, the paper shortly reviews and resumes, starting from the seminal contribution of American regionalism, the key concept of bioregional paradigm as a reference framework in theory and planning domain, especially in relation to the European context. Then, we continue by analyzing and assessing some key criticism raised to bioregionalism. Finally, the paper sets up a set of key elements to define a conceptual framework aimed to assess the “bioregional thickness” of planning and design exp eriences and spatial policies, especially in the light of actual challenges, such as climate change adaptation, local food system planning, reduction of soil consumption and urban sprawl. Key words: Bioregional planning; urban bioregion, re-embedding; self-reliance, territorialism 1. Introduction In urban planning literature and practice, a growing attention is paid to the possibilities of enhancing the interaction between rural and urban domains and ‘re-embedding' of cities within their surroundings. In this sense, the concept of ‘urban bioregion’ could play a pivotal role for appli cation in practice. Although the regionalist approach to planning emerged several decades ago, mainly in the North America context, the bioregion concepts represent a later articulation of the original concept and need to be further developed and clarified in planning domain. The bioregional framework is not a utopian project, and it not only refers to wilderness or rural areas but entails a set of key issues to foster enhanced practices for urban or peri- urban environment integrated policies, planning, and design. That turns out to be especially remarkable in the European context where city-countryside relationship historically underpinned the human settlements form and where the development was conceived as an integrated whole of nature and culture.