Definition and delimitation

The term Smart City has been used in numerous publications, vision and strategy papers, calls for funding and projects since the 1980s. There is no standardised definition, which means that the term can and usually is adapted to the respective objective being pursued.

The EU defines smart cities as cities that use technology to improve the management and efficiency of urban space[1]. In Germany, the Smart City Charter created a normative framework as a result of the Smart Cities dialogue platform (Federal Ministry of Construction) in 2017, which was updated in 2021[2]. The 73 Smart City model projects of the federal funding programme of the same name are now also based on this framework. Here, the term is introduced in the context of the digital transformation of cities, districts and municipalities and aims to find “resource-saving, needs-based solutions to the central challenges of urban development”.

Under the term Smart Country, these objectives are extended to rural areas; similar objectives can also be found under terms such as Digital City, Intelligent City, Virtual City or Ambient City.

What all these terms have in common is that they

  1. that they refer to the future: They simultaneously describe a target state that has not yet been achieved in the present and the intention to achieve this target state;
  2. recognise the opportunity that the use of technology can help to achieve this: They encourage and demand innovation and new, creative solutions;
  3. often name the city itself as an actor; who from urban society is responsible for the implementation of the smart city and who is at least involved can therefore vary greatly. These can be, for example, municipal administration, municipal utilities and other municipal service providers, local and national technology companies, associations, federations and other organisations as well as the citizens themselves.

As the Applications and examples section shows, the application domains considered in a smart city are as diverse as urban life itself. In most cases, they require interdisciplinary or transdisciplinary approaches, as there are strong interactions between the technologies used, the people and organisations involved in the respective locations and spatial conditions. One of the greatest challenges is therefore the transferability or transfer of concrete systems and solutions from one smart city to another, for which practicable answers are urgently needed for reasons of economic efficiency.


The term smart city has been used in the literature since the late 1990s [3]. Technology companies have also addressed urban processes in their corporate strategies and marketing concepts, such as IBM in 2009 as part of its Smarter Cities campaign [4]. While projects and products initially focussed on the profitable use of technologies, particularly in large cities and megacities, smaller cities and rural areas were soon also considered.

In Europe in particular, there was a shift in focus that emphasised the goal of quality of life and sustainability and no longer presented new technologies as an end in themselves, but as a useful and necessary tool.

Application and examples

The applications considered under the term Smart City relate to all aspects of urban life. According to the systematic literature study by Anthopoulos [3] smart city solutions can be found in the following domains:

  • efficient use and management of resources, such as smart energy or water management
  • Traffic management and mobility, often with a focus on intelligent and/or multi-modal services
  • urban infrastructure and improved urban planning with digital support
  • Quality of life: education, health and safety in urban areas
  • Government: public e-services, e-democracy and participation, accountability and transparency, and the efficiency of governance in the city
  • Economy: includes areas that reflect the domestic product in the city, the spirit of innovation, employment and e-commerce
  • Coherence: social issues, such as the digital divide, social relations and digital participation.

There are also examples of other domains such as tourism, environmental protection and culture.

There are also examples of other domains such as tourism, environmental protection and culture. One or more of the following components are usually found as solution components of a smart city: A centralised or federated data platform on which urban data from different domains is integrated and geo-referenced; this is often partially or even completely designed as an open data platform; one or more urban apps through which citizens or guests can use digital services; a portal for citizen participation, through which an exchange about planned projects takes place and new ideas are introduced; a mobility platform, through which mostly intermodal mobility offers (such as public transport, car parks, parking spaces, etc.) can be integrated and geo-referenced. Mobility services (e.g. public transport, parking, micromobility, sharing) are bundled and integrated either via a search or through to ticket booking; one or more sensor networks that are used to collect decentralised information about the environment (e.g. microclimate, water levels, air quality) or the condition of urban infrastructure (e.g. fill level of waste bins). Technologies that can be categorised as part of the Internet of Things are often used here. The term ” digital twin ” has been adopted from the industrial sector and can be used in very different ways in the context of smart cities – from a 3D city model to systems that enable simulations of traffic, heavy rainfall or microclimates in the city. Such systems are often supplemented or realised by participatory methods such as crowdsensing (also known as crowdsourcing or citizen science), in which citizens themselves are involved in data collection or even play a key role in driving it forward, such as in the Sensor Community [5].

Numerous cities and municipalities now have their own smart city initiatives, which have often emerged from funding initiatives, but in some cases have also been financed by their own resources. In the European context, Barcelona, Vienna, Helsinki, Amsterdam and Copenhagen are often cited as pioneers; internationally, Singapore and the Chinese city of Songdo are examples of how many areas of urban life are being organised through the widespread use of sensor technology, albeit at the expense of privacy in public spaces.

In Germany, 73 Smart City model projects [6] are being funded as experimental sites for integrated urban development. The programme runs until the end of 2027 and provides numerous other examples.

Criticism and problems

Even if the idea of a smart city is usually motivated by goals for society as a whole or in relation to the 17 global Sustainable Development Goals (SDGs), there are criticisms and challenges that should not be neglected.

In particular, the first smart city projects focussed on the use of innovative technologies without making clear the benefits for the city’s citizens and their needs. When using sensor technology in public spaces, it is always important to consider what information is collected about urban life and whether this intrusion into privacy and the right to informal self-determination can be justified by a benefit to society as a whole. It can also give the impression that taxpayers’ money is being spent on useless gimmicks while other, more pressing problems are being ignored.

Another point of criticism concerns the technological and digital sovereignty of local authorities. As smart city solutions are often not very standardised, there is a risk that a municipality with central municipal processes will become dependent on individual technology providers and burden its budget with long-term licence agreements. Migration to another provider is often technically impossible or very costly, resulting in a vendor lock-in.

The use of the technology itself (sensors, communication technology and computers) also leaves an ecological footprint; the enthusiasm for new, innovative solutions must therefore take into account not only installation but also maintenance, recycling, energy consumption and, last but not least, electromagnetic radiation. Although the latter is usually very low (also due to energy-saving IoT standards such as LPWAN, Low Power Wide Area Network), concerns about negative consequences – similar to the installation of mobile phone masts – can lead to rejection among the population.

Smart city solutions often only offer digital user interfaces (e.g. via smartphones). This increases digital inequality and makes it more difficult for entire population groups to participate in urban life. It is therefore important to also create analogue or freely accessible interaction options, e.g. through public displays or the printing of automatically generated and thus frequently updated brochures.

There are also fears that smart city initiatives will further widen the gap between urban and rural development. However, rural areas in particular can benefit greatly from the use of intelligent solutions, e.g. for mobility or the promotion of innovative jobs. The term smart city is therefore often extended to include smart country or digital villages.


Research on the smart city can be found in numerous disciplines, some of which work in isolation, others interdisciplinary and transdisciplinary, from computer science and engineering, geography, urban planning, political science or economics to psychology or philosophy. Possible research questions include

  • How can environmental parameters and urban processes such as mobility or the condition of infrastructure be measured in a cost-effective, energy-saving and data-efficient way without violating citizens’ privacy? In addition to technical and more objective parameters, qualitative or subjective factors can also be recorded, such as perceived noise pollution or the feeling of safety.
  • What influence do new urban applications have on urban life, such as the quality of life, communication between citizens, voluntary work and economic strength?
  • Which indicators and parameters are suitable for measuring and controlling the digital transformation and the achievement of objectives in the various areas of the smart city?
  • How can urban processes be optimised using digital methods?
  • How can artificial intelligence methods be used sensibly in smart city systems?
  • What ethical standards should be applied when designing smart cities? And under what conditions is a society or individuals from different groups prepared to accept this change?

One example of an inter- and transdisciplinary research network is the Smart City Research Lab [7] at the University of Bamberg. Here, scientists from various disciplines work on such issues in close cooperation with local authorities, solution providers and urban society. Depending on the objectives of the project, the stakeholders involved and the funding, different formats are suitable for this, such as joint events (hackathons, conferences, lecture series), supervision of student projects and theses, third-party-funded collaborative projects or direct research assignments. A central point here is the interdisciplinary Bamberg Graduate School of Smart City Science, which provides the necessary transdisciplinary mix of methods for these research questions in the doctoral projects.