First, an ecosystem is a complex network or an interconnected vision must itself be delivered, shared, and tested to be as system. Second, a business ecosystem pools many organizations coherent as possible with local initiatives. Second, leadership and stakeholders. Third, ecosystem members generally interact is a prerequisite for starting smart city implementations and on the basis of competition and/or cooperation, depending on being successful in advanced stages of initiatives. Third, city the matter at hand. Fourth, each entity belonging to a city’s officials need to feel empowered to act as entrepreneurs. Urban ecosystem influences and is affected by the others. Fifth, an planning and smart city programs should focus on key use ecosystem creates a constant changing of ties and relationships cases and an entrepreneurial spirit. Usually, citizens recognize among members. Being much less formal than a governance- the value of such smart city initiatives and are willing to adhere based approach, an ecosystem-based approach requires each to a good number of urban services. entity to be flexible and adaptable. The common good requires all hands on deck Citizens’ Participation vs. Centralized Decision Making. The current city experience faces social, environmental, and To make smart cities work, the key challenge is to pool infrastructural challenges. City residents must deal with initiatives and give coherence to projects. In this ebook, we have multiple challenges, from public security and transport issues identified the smart city’s stakeholders operating at different to cultural issues and long-term concerns about sustainability. levels: The promise of a sustainable future relies on a knowledgeable • City leadership and administration, as well as public sector vision. Moreover, it is critical to put citizens at the center employees; of smart and sustainable city initiatives. Success requires • Private sector companies; developing a deep understanding of the areas of life in which • Residents from all neighborhoods. inhabitants are willing to adopt smart city innovations and change their behaviors. Urban transformation will alter some A- Great smart cities’ challenges require good city parts of the urban way of life. It will require a willingness from governments citizens to pay more to access smart solutions. The aim is to attract private investors. Throughout this ebook, we have seen how sustainable city policy depends on the set of natural, geographic, economic, Centralization vs. Decentralization. National and local cultures and social aspects that condition all urban planning. However, strongly influence decision-making practices, as does the another factor also determines sustainable city policy: good ideological heritage of the team currently in public office. The city management.4 methods and processes for organizing the flow and circulation of information, which may go from top to bottom or bottom to When they began their bids to become smart cities, the six top, are strongly imbued with various core prerequisites. Among cities in our sample already enjoyed exogenous advantages— these, the type and level of participation of citizens, and of civil for example, wealth derived from economic performance, society, will be influenced (or not) in the long term. Among density (which indicates the attractiveness of a place for some key determinants, we identify the level of decentralization of people), and existing high-tech industries that were able to public decisions and the degree of involvement of people and offer the city ICT, health, energy, and mobility solutions. To be organizations. In fact, the collaborative vs. authoritarian nature sure, there are other cities in the world that lack some of these of exchanges between the different types of actors involved in advantages. However, all cities and metropolises are capable major urban issues will be dramatically important: exit the of elaborating their own visions, exercising good management, collaboration or voice the concerns and claims. and implementing urban planning policies. Successful policy also depends on a clear vision as to how to break away from the Autocracy vs. Democracy. Three factors are extremelytraditional ways in which cities have been managed. A good city important to democratic institutions: vision, leadership, and government has to understand the needs of the city’s residents entrepreneurship. First, mayors and their teams have to and meet their expectations. To do so, it must redouble the create a compelling smart city vision that has sustainability, efforts made by municipal agencies, educational institutions, resilience, and inclusiveness at its heart. For city officials, all nonprofits, private sector partners, and startups. This type of initiatives deserve to be in coherence with their vision. This engagement has the potential to change how cities are governed. (4) The Italian painter Ambrogio Lorenzetti (1290-1348) foreshadowed this concept in his painting The Allegory of Good and Bad Government, a set of three fresco panels painted between February 1338 and May 1339. These paintings are permanently located in Siena’s Palazzo Pubblico. The three masterpieces are made of six different scenes: Allegory of Good Government, Allegory of Bad Government, Effects of Bad Government in the City, Effects of Bad Government in the Country, Effects of Good Government in the City, and Effects ofGood Governmentin the Country. https://en.wikipedia.org/wiki/The_Allegory_of_Good_and_Bad_Government; https://www. visittuscany.com/en/attractions/siena-ambrogio-lorenzetti-good-and-bad-government/ (Accessed on 20 April 2021). 230 Quélin and Smadja | HEC PARIS | SMART CITIES | The sustainable program of six leading cities | 2021