Abstract

The rapid rise of city digital twins has been accompanied by ambitious claims. These dynamic, data-rich representations of urban environments are promoted as powerful tools for creating smarter, more efficient and inclusive cities. They are expected to support better decision-making, increase transparency, and enable citizens to engage more closely with the planning processes that shape their everyday lives and cities (Haraguchi et al., 2024). Yet, the reality on the ground is far more complex and far less transformative than the rhetoric suggests. At the heart of the issue lies a fundamental tension. While digital twins are framed as tools for inclusion, they are largely developed, operated, and interpreted within expert-driven environments. A survey we conducted in September 2024, with 55 expert responses, revealed that although these tools are widely used to inform (78%) and consult (82%) with communities, they rarely enable genuine participation in decision-making. The opinions were mixed regarding the effectiveness of city digital twins in delegating decision-making power to communities. 1 In other words, digital twins are helping cities talk to citizens but not necessarily listen to them.
The expert responses indicated diverse perspectives on the nature of city digital twins. These findings highlight their conceptual and practical diversity. At least three overlapping user groups can be identified, each characterised by distinct interpretations and operational approaches. First, there are the city digital twin technicians who build and operate these systems. In practice, these are often data scientists, modellers, and analysts who deal with data integration pipelines and spatially explicit representations and simulations of urban phenomena. For them, the digital twin is primarily a computer model, a system to be calibrated, validated, and optimised. Their focus lies in data quality, interoperability, and modelling accuracy (Batty, 2024; Gil et al., 2024; Van der Laag-Yamu et al., 2023). Next, there are the city digital twin theorists who shape and participate in the broader discourse. These include academics, researchers, and conceptual thinkers who frame digital twins as socio-technical systems, governance tools, or even political instruments (Nochta et al., 2021). For this group, the digital twin is less a tool and more of a conceptual lens through which to interrogate questions of power, knowledge, and urban futures. The last group are urban digital twin consumers who seek to use digital twins to achieve practical outcomes. These include planners, policymakers, consultants, and entrepreneurs who use digital twins as instruments to support planning decisions, communicate with stakeholders and citizens or drive innovation and policy outcomes (Bonin and Frankhauser, 2025; Wan et al., 2024).
Importantly, these user groups are not mutually exclusive. As the survey data reveal, many respondents hold multiple roles simultaneously. For example, project managers who also serve as data specialists, researchers who provide policy advice, or practitioners who engage in conceptual debates. This overlap is not accidental, and it highlights the inherently hybrid and complex nature of digital twin ecosystems. An individual may navigate between building models, interpreting them, and applying them in decision-making situations. Although a single person may perform multiple roles, the logic tied to each user group remains separate
These differences are not merely semantic, and they shape how digital twins are designed, implemented, and used. Technicians may prioritise model sophistication over accessibility. Theorists may emphasise critique without always engaging with operational constraints. Consumers may focus on usability and outcomes, sometimes without fully understanding the underlying assumptions embedded in the models that they rely on. This divergence helps explain one of the study’s central findings: the persistent gap between the promise of participation and the reality of practice. If city digital twins are built primarily through the lens of technicians, they risk becoming unrealistically ‘data-hungry’ and overly complex; this especially impacts the human interactions with the digital twin and subsequent decision-making. If shaped mainly by theorists, they may remain conceptually rich but practically underdetermined. If driven solely by consumers, they may prioritise immediate usability at the expense of transparency and methodological rigour.
In practice, current implementations appear to be dominated by technical and expert-driven logics. This is reflected in the limited use of standardised protocols (only 21%), the strong emphasis on data and modelling, and the reliance on expert interpretation (Van der Laag-Yamu et al., 2023). As a result, participation tends to remain at the levels of information and consultation, rather than evolving into genuine co-decision or power-sharing. Importantly, the German Institute for Standardisation (DIN – Deutsches Institut für Normung) published DIN SPEC 91607 (2024) to close this gap. This standards guideline provides a comprehensive overview of urban digital twins, defining requirements for their use in cities and municipalities, and serves as a guideline for users. Its main intention is to establish a framework for uniform communication and information on urban digital twins, ensuring comparability and transparency. This guideline aims to enable users to achieve interoperability, investment security and scalability. While DIN 91607 represents an important step towards standardisation and improved interoperability, it primarily addresses the technical and procedural dimension of urban digital twins. As such, there remains a need to address underlying challenges related to participation, knowledge integration, and governance. The persistence of expert-driven approaches suggests that the limitations identified above are not merely a consequence of missing standards but stem from deeper structural and epistemic divides within the development and application of city digital twins.
To move forward, cities must recognise that digital twins are not neutral tools but rather meeting points for different forms of expertise, interests, and expectations
What, then, should cities do? First, they must reframe digital twins as governance tools rather than merely as technological platforms. This means embedding them within existing institutional structures, with defined responsibilities and accountability mechanisms that reflect the diversity of actors involved. Second, cities need to design participation across all three user groups
The broader lesson is clear here. Technology alone does not transform governance. Digital twins may offer new ways of seeing the city, but they do not automatically change who gets to shape it. If anything, they make existing power differences more visible between those who build, those who theorise, and those who use. In the end, the question is not whether digital twins can model the city with increasing precision. The question is whether cities can bring together these different communities of practice to govern more inclusively. Without that, the smart city risks becoming not a more democratic city, but simply a more sophisticated version of the existing governance and power structures.
Studies and critical reflections in this special issue
This special issue, ‘Digital Twins for Cities – Perspectives, Methods and Applications’, brings together seven research articles and commentaries that provide a comprehensive and critical overview of city digital twins (CDTs)/urban digital twins (UDTs), moving beyond purely technical perspectives to position them as socio-technical tools for urban planning, governance, and decision-making. In parallel with technological innovation, contributions highlight the continued importance of theory, domain knowledge, and causal understanding for meaningful policy support. Multiple contributions show that urban digital twins are shaped by stakeholder interactions, participation processes, and power dynamics, rather than being neutral tools. They also highlight the potential for co-creation processes. Furthermore, advanced methodological innovation is presented by a range of approaches, including ontology-based frameworks, federated data architectures, agent-based modelling, and multi-scale spatial modelling. These approaches aim to improve interoperability, integrate human behaviour, connect multiple scales, and enable more adaptive, stakeholder-specific applications of digital twins. At the same time, empirical and applied contributions – such as the participatory case of Gothenburg – demonstrate how digital twins can support scenario exploration, urban decarbonisation strategies, and real-world decision-making, while also revealing challenges related to usability, data quality, and trust. Finally, the special issue highlights the future potential of digital twins as platforms for experimentation and learning, enabling iterative policy testing, real-time feedback, and exploration of alternative urban futures. For the readership, this special issue offers (Table 1): • An overview of current developments in urban/city digital twins • A critical perspective on their limitations and risks • Conceptual frameworks and methodological innovations for advancing the field • Practical insights and case-based evidence for implementation in planning contexts Overview of research and articles published in this special issue.
Overall, it equips researchers, practitioners, and policymakers with a more nuanced understanding of digital twins as socio-technical infrastructures and provides guidance on how to develop and use them in ways that are not only technically robust but also socially meaningful and governance-relevant.
Concluding remarks
The field of research has already expanded, with a growing number of studies in which new frameworks combine artificial intelligence with real-time data and physics-based modelling for applications such as pollution prediction and climate risk assessment (Dorostkar, 2025; Teutscher et al., 2025). The paradigm shifts towards predictive and adaptive systems. The use of city digital twins has now arrived in climate action and urban resilience, including energy systems, climate adaptation, infrastructure resilience, and environmental monitoring, linking these advanced models to, for example, coastal resilience planning, climate risk mapping, and decarbonisation strategies that integrate equity considerations (e.g. energy poverty) (Bibri et al., 2025; Chen et al., 2025; Shen and Zhou, 2025). We also find advances in data fusion, interoperability, and real-time integration across systems. Recent research explicitly connects building information models (BIMs) with city digital twins (CDTs) to form holistic city information models (CIMs) (Shi et al., 2023). Thus, multi-scale systems and system-of-systems approaches are outdating single-scale models, alongside the rising demand for human-centred and participatory urban digital twin development. This is further accelerated by the current boom of artificial intelligence in both research and practice. However, despite the artificial intelligence revolution, the human-centred and participatory digital twin is still evolving.
As the participation gap persists, this special issue demonstrates that city digital twins are at a critical juncture. While they hold significant promise as tools for improving urban planning, decision-making, and stakeholder engagement, their current development remains uneven and often constrained by technical and expert-driven logics. A central insight emerging from both the contributions and the broader reflections is the gap between the promise of participation and the reality of its practice. To move forward, cities must therefore rethink the role of digital twins – not as neutral tools, but as arenas where different forms of knowledge, interests, and expectations intersect. Technology alone does not transform cities or governance. City digital twins offer increasingly sophisticated ways of representing urban environments, but their value lies in how they are embedded within social, institutional, and political processes. Key challenges and the pathway to the triumph of city digital twins (borrowed from Glaeser`s triumph of the city, 2011) is to ensure that the processes through which they are understood, debated, and shaped become more inclusive, transparent, and collaborative.
Footnotes
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was provided by the European Union’s Horizon Europe research and innovation programme via the projects CROSS-REIS (Grant agreement No 101136834) and JUST STREETS (Grant agreement No 101104240).
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to research, authorship, and/or publication of this article.
