This paper presents the findings of an interdisciplinary academic exchange exploring the transition towards a circular built environment (CBE), developed over two years of collaborative work at Delft University of Technology’s Circular Built Environment Hub. A key outcome of this work is developing a comprehensive definition of the CBE and the related Scales to Aspects model, which connects the multi-scalar and cross-disciplinary nature of circularity, ranging from materials and components to buildings, neighbourhoods, cities, and regions. It highlights critical tensions, such as the lack of integration between circular strategies and other global challenges.

Manufacturing and housing in urban areas are related. The aim of this chapter is to critically contextualize the causality of why we need housing in cities. Causality describes the relationship between cause and effect. In this context, living in the city is seen as an effect of a certain cause, but this cause evolves over time and with geographic development. This chapter proposes that we are at the beginning of a new era where the cause for needing housing in the city is changing. This shift could be particularly significant for Dutch cities. The central message of this chapter is that it is necessary to both acknowledge this potential change and understand its implications for transforming buildings and areas into housing in practice. This leads to the central research question of this essay: What is the role of urban transformation today for the future development of cities?

To answer this question, a brief description will first be provided of how the city can be seen as a causal result of a societal need for added value. This explains why certain cities emerged, disappeared, or adapted for specific reasons. Next, the industrial city will be discussed as a significant turning point for the role of cities in modern society. Following the description of the post-industrial city, it will be explained that the heyday of this era is likely over, suggesting that the reasons for needing to live in the city may change. The chapter will conclude with an answer to the research question.

Purpose
Owing to the many involved stakeholders, major challenges in the transition to a circular construction (CC) sector have an organisational nature. This study aims to better understand how intra-organisational changes can advance the transition.

Design/methodology/approach
The Delft University of Technology’s (TU Delft) circular campus ambition serves as a single case study. Construction projects are examined through desk research and interviews. Barriers to circular strategies are analysed using a framework that combines the R-Ladder for hierarchies of CC practices with organisational levels used for transition management.

Findings
Most barriers occur on the operational and tactical level, while most possible interventions are located on the tactical to strategic level. Current endeavours mostly target mid-R-Ladder strategies at the operational and tactical level. The linear accounting and project development frameworks remain significant tactical barriers within the campus real estate and facility management (CRE&FM) department. Moreover, strategic tooling such as consistent monitoring and forward dashboarding is lacking. Furthermore, CRE&FM is leading the implementation but is dependent on its parent organisation, in which measurable goals, understanding of their implications, as well as a circular financial framework, are largely missing.

Practical implications
The study provides valuable insight and practical recommendations for (semi-)public RE owners to support the CC transition from within their organisation.

Originality/value
This study advances knowledge on intra-organisational transition management and offers a new analysis framework that combines circular strategies and different management levels.

This article aimed to assess the potential impact of policy actions to support mass timber construction through an ex ante policy analysis in Amsterdam. Through a combination of policy coherence analysis and agent-based simulation, the study evaluates 130 policy actions, including 80 specific instruments, for the transition from traditional masonry to mass timber construction. The coherence analysis reveals a predominance of regulatory instruments (62%) and a lack of active economic measures (16%), which limits their impact on circular city development. The simulation tested three instruments - demolition notification, a mass timber subsidy proxy and a carbon tax proxy - to assess their individual and combined effectiveness. Isolated measures, such as material price adjustments, were found to be insufficient due to systemic inertia. However, the combination of subsidies and carbon taxes proves more effective, significantly increasing the uptake of mass timber construction as its cost is reduced and construction companies develop expertise. A key finding highlights the complementary role of recycled concrete in supporting mass timber construction, highlighting the need for integrated policies targeting both mass timber and secondary materials. Improving industry knowledge and expertise is identified as a transformative approach to reducing costs and overcoming barriers to adoption. This research is the first contribution to demonstrate the value of ex ante policy evaluation and agent-based simulation in formulating coherent and effective policies for circular city transitions. Policy makers in Amsterdam and other Dutch cities are advised to implement synergistic instruments, support local material reuse and invest in capacity building to achieve carbon neutrality and resource circularity in urban construction. The findings provide actionable guidance for Amsterdam and similar cities seeking to promote sustainable and circular urban environments.

This paper enacts a dialogue between planning literature on polycentric urban regions (PUR) and port geography literature on multi-port gateways. The main proposition is that polycentric systems are the emergent outcome of the interactions between three dimensions of polycentricity: morphological, functional and institutional. The focus is on the Dutch?Belgian Amsterdam?Rotterdam?Antwerp (ARA) port?industrial region: one of the world?s largest concentrations of oil refining and petrochemical activity. The central question is to what extent is the ARA region a polycentric system and what explains this observed polycentricity? Our analyses demonstrate a high degree of morphological and functional polycentricity with each of the constituent (firms located in) ports connected through flows and specialization in processing and trading oil (products). However, this is not the intended result of formalized spatial planning, nor did the ARA ever became a frame of reference among planning agencies. Rather, it is the result of self-organization in the oil industry that has culminated in the emergence of the ARA as an internationally recognized spot market, later institutionally formalized in delivery contracts (oil futures) traded on international commodity exchanges. We conclude that polycentric systems could be understood as emergent systems that obtained generative capacities, in turn influencing its different constituting dimensions.

Schellekens en Fernandez (2024) tonen in ESB dat de Nederlandse energie-intensieve basisindustrie minder investeert en ze pleiten daarom voor het stopzetten van overheidssteun. Elders binnen het complementaire productienetwerk Amsterdam–Rotterdam–­Antwerpen wordt echter wel geïnvesteerd. Dat vraagt om een internationale ecosysteembenadering in plaats van enkel nationale industriële strategieën. [...]

De Nederlandse bedrijventerreinen zijn van belangrijke waarde voor onze economie. Ze huisvesten een breed scala aan sectoren en bieden werkgelegenheid aan een groot deel van onze beroepsbevolking. Het zijn ook de plekken waar maatschappelijke transities zoals duurzame energie, netcongestie en circulaire economie de ruimte krijgen. Tegelijkertijd staan deze werklocaties onder druk door de groeiende ruimtevraag voor wonen, infrastructuur en natuur. Het afgelopen jaar heeft de Adviesraad van de Stichting Kennisalliantie Bedrijventerreinen Nederland (SKBN) zich geconcentreerd op het thema Beter Benutten van Werklocaties. Dit document vat de inzichten, uitdagingen en oplossingsrichtingen samen en biedt een strategisch kader voor de toekomst. [...]

One of the five circular economy (CE) principles is “localisation” or “localism”, understood as a smaller geographical consumption–production system that fits better with local needs. Rightfully, the rationale for localism is derived from ecological principles. However, these arguments remain debated and subsequently can fail to become operationalised in policy goals and measures. From a governance perspective, localism is perhaps the most important CE principle, as it is the only one that clearly links the circulation of resources to a confined area, and so to specific administrative areas, and eventually informs us “who is responsible”, and so will have the advantages, but also the disadvantages, of CE. In this chapter, we turn our attention to the European context, where the European Union (EU) and many of its member states have set out an ambitious policy agenda for moving towards CE. We argue that the current geopolitical turmoil provides a “window of opportunity” through which to clarify the responsibilities for driving a transition towards CE across levels of government and to seize the momentum to operationalise the localism principle and move European cities and regions towards more resilient, circular futures.

Circular economy (CE) is territorialised. Economic activities are spatially embedded; they operate across a variety of scales and are heavily influenced by their spatial context. Yet the CE academic literature and policy frameworks rarely address this dimension. If CE policies are to achieve sustainable development goals and be implementable at a subnational level, these shortcomings need to be addressed. In this chapter, we take stock of the current debates and policy on CE in cities and urban regions, critiquing them from a spatial, socio-ecological and governance perspective. On that basis, we outline a new policy and research agenda to bridge the above-mentioned gap and inform the development and implementation of place-based CE policies.

The circular economy (CE) brings many opportunities, but also many challenges for ports, cities, and their hinterland. The goal of this paper is twofold. First, we embrace the inherent uncertainty of the spatial impact of the CE on ports and cities. We employ scenario methodology to guide us in steering this uncertainty by developing four scenarios. To explore the complexity of these four scenarios, we focus on the Dutch province of South-Holland. This region hosts the port of Rotterdam, the largest port in Europe, and its direct hinterland consists of a dense urbanised region. As such, the four scenarios cannot only shed a light on the future of the port, but also how its relations with its direct urbanized hinterland can potentially change. In two scenarios deglobalisation occurs. The consequences are, on the one hand, that the port's focus changes more to its direct hinterland instead of a global oriented focus. On the other hand, the existing water bound industrial areas in, or nearby cities increase in importance, in contrast to the contemporary pressure to redevelop these into waterfront residential and commercial areas. In other words, port and city/region grow towards each other. The second goal of the paper is to dive into the specific consequences of these scenarios for day-to-day planning practices. By combining micro-economic and AIS shipping data, we discovered the most important terminals and industrial areas for the transition towards a CE in port, city, and hinterland.

A geographic information system (GIS) stores, manipulates, analyses, and visualises spatial data. GIS enables the mapping of building elements and components and can optimise the location of facilities for circular activities, thus contributing to the closing of material loops and the spatial development of circular cities and regions. This chapter presents use cases of GIS in the circular built environment, with examples from academia, industry, and government. Academics use GIS data for urban mining studies to estimate the location and availability of secondary construction materials. Businesses in industry use GIS analysis to inform the facility location of circular construction hubs and (reverse) logistics. Governments use GIS to monitor and assess the circular spatial development potential of their (industrial) territories. In order to integrate GIS into circular economy solutions, improvements need to be made in making spatial data available and in presenting findings that emerge from it. Finally, present enthusiasm for GIS tools should be balanced by a deeper understanding of the connection between digital tools and governance decisions.

This deliverable is the outcome of Task 1.1, Theoretical and Conceptual Framework, within
the FABRIX project’s Work Package 1, Theory and Methodology. The document lays out a
comprehensive framework to guide research across the project, which aims to establish
sustainable, regenerative textile and clothing (T&C) ecosystems through local, circular
manufacturing systems in urban areas. By integrating spatial sciences, industrial symbiosis,
and economic geography, FABRIX addresses the fragmented nature of current urban
manufacturing practices and seeks to bridge gaps between economic networks and spatial
environments.

At its core, FABRIX emphasizes the dual concepts of ‘network of spaces’ and ‘space of
networks’ to explore how urban planning and economic systems can mutually support the
shift towards circular and regenerative practices in the T&C sector. The analytical focus is
on rethinking the spatial and network relationships that structure urban manufacturing,
with an emphasis on creating sustainable frameworks that can be scaled across European
cities. The project’s evaluative dimension will assess interventions in urban manufacturing
spaces, identifying spatial configurations that promote or hinder circularity.

Central to the instrumental dimension of FABRIX is the development of the MANTEL
platform, a digital platform of tools that enhances local stakeholders’ capacity to manage
and improve value chains along circular and regenerative pathways. MANTEL targets
facilitators, businesses, and public authorities, equipping them with tools to implement
circular production and foster socioeconomic resilience.

This closing chapter brings together the main messages from each chapter. It formulates a policy agenda for circular cities and regions. It does so by providing a set of recommendations for policy practice. These are addressed at authorities and policy stakeholders at the international, national and subnational levels.

Deliverable 1.2, part of WP1 ‘Theory and Methodology’, outlines the methodologies
developed and used for the FABRIX project, which aims to foster the creation of circular
and regenerative textile and clothing (T&C) ecosystems in urban environments. This
document is a continuation of the theoretical and conceptual framework laid out in
Deliverable 1.1, building a bridge from theory to practice. The FABRIX methodology is
designed to integrate spatial design, industrial symbiosis, and value chain analysis to
support the development of localized, circular manufacturing systems.

At the core of the methodology is the exploration of two interrelated concepts: the "space
of network(s)" and the "network of space(s)." These concepts guide FABRIX in addressing
the complex relationships between spatial and economic factors in urban manufacturing.
The project examines how these systems interact and how they can be optimized to
support circular and regenerative production processes, particularly in the cities of Athens
and Rotterdam. Through this approach, FABRIX aims to uncover key insights about how
networks of actors, resources, and institutions can drive local innovation while responding
to global challenges.

The methodology is operationalized through several key stages. These include the
mapping and scoping of existing T&C ecosystems, a visualization methodology that
combines topological and spatial data, and the development of a relational database to
analyse the interaction between various actors and their relationships. Additionally,
interviews with stakeholders—government officials, facilitators, and businesses—will
provide qualitative insights that inform the development of the MANTEL platform, a
digital platform of tools designed to support and guide local value chains by enhancing
collaboration and problem-solving capabilities for facilitators and public and private policy
makers.

FABRIX’s methodological approach emphasizes a co-creation process, with ongoing
interaction and feedback loops between the research team and local stakeholders.
Through open calls, financial support, and workshops, the project will directly engage
facilitators and businesses, empowering them to adopt circular practices and build
collaborative networks. This participatory approach ensures that the solutions developed
are not only theoretically sound but also practically viable in real-world settings.

Bedrijvigheid en wonen in de stad zijn met elkaar verbonden. Doel van dit hoofdstuk is de causaliteit van waarom we woningen in de stad nodig hebben kritisch in context en tijd te plaatsen. Causaliteit beschrijft de relatie tussen oorzaak en gevolg. Wonen in de stad wordt hier als een gevolg gezien van een bepaalde oorzaak, maar deze oorzaak verandert door de tijd en geografische ontwikkeling heen. De propositie van dit hoofdstuk is dat we aan het begin staan van een nieuw tijdperk, waarin de oorzaak waarom we woningen in de stad nodig hebben, verandert. Vooral voor Nederlandse steden zou dit weleens een belangrijke verandering kunnen zijn. De centrale boodschap van dit boekhoofdstuk is dat het daarom nodig is om deze mogelijke verandering ten eerste niet (impliciet) te negeren, en ten tweede de mogelijke gevolgen goed te begrijpen wanneer we in de praktijk in steden gebouwen en gebieden transformeren naar woningen. Dit leidt tot de centrale onderzoeksvraag van dit essay: Wat is de rol van stedelijke transformatie vandaag voor de ontwikkeling van steden in de toekomst?

Om deze vraag te beantwoorden, zal eerst een korte beschrijving gegeven worden van hoe de stad gezien kan worden als een causaal gevolg van een maatschappelijke noodzaak aan toegevoegde waarde. Dit verklaart waarom bepaalde steden om bepaalde redenen ontstaan zijn, verdwenen zijn, of zich aangepast hebben. Vervolgens wordt de industriële stad uitgelegd als een belangrijk kantelpunt voor de rol van stad in de moderne maatschappij. Na de beschrijving van de post-industriële stad, wordt uitgelegd dat de hoogtijdagen van dit tijdperk hoogstwaarschijnlijk voorbij zijn, en dat dus de oorzaak van waarom we wonen in de stad nodig hebben weleens zou kunnen veranderen. Het hoofdstuk eindigt met een conclusie waarin een antwoord wordt geformuleerd op de onderzoeksvraag.

As circular economy policies are adopted to tackle unsustainable built environment patterns related to carbon emissions and inefficient use of resources, scholars warn about the inadequacy of such policies to support sustainable urban development. Siloed circular economy policies in the built environment have focused on applying circular strategies to construction practices. However, cities as complex adaptive systems require systemic interventions including ecologically regenerative and adaptation actions to bring about a more circular built environment and, ultimately, a circular city. This article analyses policy coherence –or the (mis)alignment and possible synergies– of circular built environment in Greater London. Resorting to a circular city policy coherence framework, through document analysis of planning and circular economy policies and semi-structured interviews, both the state of circular built environment policy is assessed and policy recommendations are provided. Circular built environment policies in Greater London have increased in their overall coherence by means of the application of circular economy principles in construction practices, but less so in bringing about a circular city. The findings contained herein may inform policy making in Greater London and other cities of the world to help improve their circular city policy responses to the complex societal challenges imposed by the ongoing socio-ecological crisis.

This chapter applies the polycentric port region perspective on the US Gulf Region. This concept, which originates from urban studies, has recently been adapted by Van den Berghe et al. (2022) to study multiport gateway regions, with focus on the European Amsterdam-Rotterdam-Antwerp (ARA) petrochemical port region. The central research question is if and to what extent the US Gulf Region is also a polycentric port region. To do this, we analyzed the three dimensions of polycentric port regions: morphological, functional, and institutional. Based on Automatic Identification System (AIS) shipping network data, geographical mapping, and institutional historical analyses, our empirical results show that the US Gulf Region can be regarded as an emergent polycentric port region. Although there are important differences with ARA, also the US Gulf port region exists of a set of different port regions where several different petrochemical functions are located and that are functionally related. In other words, to some degree, but less than ARA, specialization and complementarity is in play. In line with the ARA region, the emergence of the oil spot market is an important moment. For the US, the physical delivery point is in Cushing, Oklahoma, and not along the coast, which differs to ARA. Nevertheless, we conclude that both regions – being the first and second most important petrochemical regions in the world – are polycentric and on top of that have important relations between them. With the current shocks in the energy market, using such perspective can help us understand what is happening or will occur in these regions; not the least in reference to the hydrogen and post-fossil chemical sector.