More than half of the world’s population lives in urban areas, which accounts for 80% of GDP (United Nations, 2015). Quite clearly, cities are the major engines of economic growth; however, they are also responsible for 80% of global energy consumption, 75% of natural resource consumption and 75% of CO2 emissions (United Nations Environment Programme, 2013). Nonetheless, cities have been described as catalysers and arenas for change from unsustainable to more sustainable lifestyles. One such catalyst for change is the emerging phenomenon of sharing, seen as a means to address current unsustainable patterns of production and consumption by utilising the idling capacity of our material world. Although sharing has been a traditional form of exchange in human history, its interest to researchers has recently resurfaced as new forms of sharing are now emerging among strangers, enabled by digital technologies and social media. Sharing, constituted today as the ‘sharing economy’, often includes some form of payment or exchange to enable access to underutilised goods and services, skills and spaces. An annual growth rate exceeding 25% is predicted to continue for years to come as there is increasing focus on sharing, especially with the success and subsequent regulations of platforms like Airbnb and Uber (European Union, 2013). As such, sharing organisations are increasingly involved in vital sectors of the economy, including accommodation, transportation, consumer goods and financial markets. Indeed, five sectors of the sharing economy are estimated to generate $335 billions in global revenues by 2025 (PwC UK, 2014).

The sharing economy has been praised for being a sustainable alternative to the current untenable thinking of infinite economic growth (Heinrichs, 2013). Proponents claim that sharing has the potential to cope with new realities of continued economic recession, job shortages, governmental austerity, increasing income inequality and growing environmental problems associated with consumption. It is argued, sharing may: reduce environmental impacts by putting underutilised assets to work; generate economic revenue from urban assets; and, improve social cohesion by connecting individuals via ubiquitous digital technology. Opponents warn that there is little evidence to support the sustainability claims of sharing organisations. They maintain that awaited environmental effects failed to materialise and that economic benefits are not equally distributed among societal actors. Concerns have been raised about public safety, individual privacy, labour laws, and limited liability among sharing organisations. Thus, before cities can fully embrace sharing as a way towards a more sustainable future, the sustainability impacts of sharing organisations need to be systematically evaluated.

Since Urban Sharing concerns the impacts and institutionalisation of the sharing economy in cities, the terms urban sharing and urban sharing organisations (USOs) are used. USOs do not operate in a vacuum – their design, operations and sustainability impacts are affected by cities and the broader institutional contexts. City governments may facilitate, enable, ignore or inhibit urban sharing. Different institutions and urban actors may influence sharing in various ways in different cities. Therefore, many urban sharing organisations face the challenge of institutional complexity, where divergent institutional logics coexist, merge, or are in conflict with each other. However, literature provides few insights into how USOs become institutionalised in diverse urban contexts, how they deal with institutional complexities, what role cities play in shaping the landscape of urban sharing, and how institutionalisation paths influence sustainability impacts of USOs.

Urban sharing is a growing global phenomenon with the potential to dramatically impact the current economic paradigm and enhance sustainability in cities. But, the lack of evidence to support the sustainability promises and the limited theoretical understanding of their institutionalisation pathways in different urban contexts, calls for a comprehensive analysis of urban sharing organisations and urban sharing phenomenon.