Making the Unsustainable Sustainable: Towards a Transitions Management Perspective of Housing Development in England

1. Introduction

The ongoing challenges associated with housing and development in the UK remain persistent and deeply contested. The dominant rhetoric seems to be set by large national housebuilders, offering a simplistic reductionist narrative based primarily around ‘units’ required [1]. Yet, housing and development is a complex and multi-faceted issue, with competing agendas and pressures set against the broader discourse of sustainable, healthy and inclusive communities for all. In practice, a focus on units prioritises short-term deliverability that speaks to a small number of supply-side stakeholders, rather than to the creation of long-term sustainable, healthy and inclusive communities [1]. This logic is reproduced through planning negotiations, finance underwriting, and project governance norms, creating path dependency that makes place-oriented approaches appear optional or non-essential rather than foundational. As a result, development outcomes frequently fall short of broader societal, environmental, and economic objectives.

The research outlines an alternative approach in the form of the recently created system architecture for a Place Building System (PBS). The PBS is fundamentally driven by the development of thriving, inclusive, walkable, healthy and sustainable places, and is the outcome of a collaborative Knowledge Transfer Partnership (KTP) project funded by Innovate UK [2]. The PBS represents an integrated system that supports the delivery of inclusive housing, mixed-use development, community participation, and sustainable infrastructure delivery, highlighting the potential to transform neighbourhoods, enhance community wellbeing, and foster long-term resilience [2].

While elements commonly associated with place-building (such as walkability, sustainability, and mixed-use development) are increasingly referenced within contemporary schemes, they are often incorporated in a partial or fragmented manner, rather than embedded as foundational principles from the outset [3]. Yet, the PBS faces a very real and often underestimated challenge of how uptake and scaling of the system might unfold. With the built environment sector being littered with improvement agendas and initiatives that often fail to gain traction or realise their potential, consideration of uptake and scaling is vital. Whilst critique of the PBS creation process has been explored [2], its adoption is shaped by the wider landscape within which it operates. Understanding how such an approach might move beyond a conceptual or pilot stage, and begin to influence mainstream practice, is therefore central to this research.

The paper is structured as follows. The research problem is presented as two sides of the same coin: firstly, the need to take a different approach to housing development, led by a place-building paradigm rather than a dogmatic focus on ‘units’ built; and secondly, the challenge of how the required transitional change within the housing development sector might be brought about, including how uptake and scaling might be played out. A critique of the interconnected literatures is offered, illustrating the complexity of the topic, the institutional logics that shape current practice and the headwinds any new approach may face. The MLP transitions management framework is introduced, drawing upon Geels’ seminal work on technological transitions and the Multi-Level Perspective [4]. This explanatory framework is unpacked, illustrating how it may explain transformations across sectors. Focus then turns to unpacking how uptake and scaling of the PBS might be explained and identifying potential actions that could support this. Summarising thoughts focus upon agency enacted across levels and being primed and ready for when opportunities arise to reshape the national housing development sector.

2. Research Problematic

Transitions within the built environment, or more specifically the housing and development sector, are arguably less constrained by a lack of compelling vision or innovation and rather by the institutional structures that shape how development is currently conceived and delivered. Unpacking that, the existing financial models, regulatory frameworks, entrenched planning paradigms and stakeholder agendas create powerful path dependencies that limit the sector’s capacity to adopt alternative approaches [5]. Such institutional arrangements are designed to maintain continuity, manage risk, and support volume delivery, and hence inhibit the uptake of innovations (like the PBS), even when the social, environmental, and economic benefits are well evidenced. Such characteristics are commonly associated with stabilised socio-technical regimes, where institutional arrangements reinforce practices and limit the capacity for alternative approaches to gain traction [6].

Planning practice exemplifies such challenges, still dominated by forecasting approaches that extrapolate future development from present-day norms and constraints. While effective for operational stability, forecasting approaches tend to reinforce the institutional logics of the time that produced the shortcomings in the first place. These institutional dynamics also shape the incentives and decision-making environments of key actors including planners, developers, funding bodies, policymakers, influencing how innovations are interpreted, supported, or resisted in practice. Typical examples relate to the water infrastructure crisis in the UK, whereby structural institutional failings have caused untold damage to humans, wildlife and the natural environment. Thus, privileging piecemeal incremental end of pipe action (or cover up) over meaningful systemic change continues to only preserve a flawed system. Consequently, innovations (such as PBS) that propose a systemic shift struggle to gain legitimacy within processes calibrated to prioritise efficiency, compliance, and short-term deliverability.

With the PBS reaching a point of stabilisation through collaborative development, the research problematic now shifts to navigating deeply embedded organisational routines, regulatory expectations, investment logics, and professional practices that collectively shape how uptake and scaling is enacted or constrained. Providing an understanding of how this uptake may occur and under what circumstances is the focus of the research.

3. Housing Development Landscape

In the UK, housing development is a highly emotive topic, typically framed in terms of crisis and commonly presented as a problem of insufficient supply or too few units being built. Such interpretations oversimplify what is in fact a contested and structurally complex arena. Housing provision in England operates within a challenging space shaped by competing political priorities, complex financial and market logics, institutional fragmentation, and uneven spatial development [7,8]. Persistent under-delivery therefore reflects not merely quantitative shortages but deeper systemic tensions involving land ownership patterns, speculative investment practices, infrastructure deficits, and the concentration of delivery power among a limited number of volume housebuilders [1]. These dynamics produce distributive outcomes that exacerbate affordability pressures and spatial inequality, demonstrating that housing provision is embedded within broader political-economic structures that constrain effective reform.

In recent policy discussions, housing need in England has frequently been framed around a benchmark of approximately 300,000 new homes required annually [9], yet completions have consistently fallen short of this benchmark. Revisions to the National Planning Policy Framework (NPPF) and the standard method for assessing housing need suggest a requirement closer to 370,000 homes annually with housing growth directed towards areas experiencing the greatest affordability pressure [10]. These recent reforms to the NPPF [11] further illustrate attempts to recalibrate housing delivery toward affordability pressures; however, such policy adjustments continue to operate within an existing regime logic that prioritises output over integrated place outcomes.

While shortfalls are often interpreted as evidence of planning system inefficiency, a more critical perspective highlights the interaction between regulatory constraints, infrastructure funding gaps, community resistance, and market absorption strategies that collectively shape delivery rates. Repeated reforms of the planning system over recent decades have not resulted in housing delivery at the scale required, indicating that the constraints on housing production extend beyond regulatory frameworks alone [12]. In particular, the rate at which homes are brought forward is constrained more by the limited rate at which local markets can absorb new housing than by planning permissions or land availability alone [13].

Conventional economic reasoning suggests that rising house prices should stimulate increased housing construction, as higher prices relative to income signal shortages and incentivize additional supply. However, empirical spatial analysis indicates that patterns of new housing construction do not consistently align with areas experiencing the greatest affordability pressures, or market stimulation suggesting a disconnect between theoretical supply responses and observed patterns of housing delivery [14]. In this context, housing emerges as a space of negotiation and conflict rather than a purely technical supply problem, with development outcomes influenced by risk management practices, profitability thresholds, and local political dynamics. The cumulative deficit generated by these constraints has intensified affordability pressures and placed sustained strain on both private and social rental sectors, reinforcing patterns of exclusion and housing insecurity.

This growing recognition of housing as a structurally constrained system is reflected in the New Towns Taskforce Report to UK Government published by the Ministry of Housing, Communities and Local Government [15]. The report advances large-scale, master-planned settlements as a mechanism for unlocking supply while considering wider economic and community objectives. However, the report’s emphasis on integrated delivery also implicitly acknowledges the limitations of fragmented development models that have historically prioritised short-term output over long-term place quality. This aligns with wider design-policy learning on the importance of integrated design quality and place outcomes, including lessons from the National Model Design Code pilot programme [16]. By advocating the integration of housing, employment, transport connectivity, and social infrastructure from the outset, the Taskforce recognises that housing delivery is inseparable from broader spatial planning and infrastructure coordination challenges.

Lessons drawn from historic new town programmes and contemporary garden-city initiatives further emphasize the structural difficulties embedded within large-scale development. The Taskforce underscores the importance of early social infrastructure provision, coherent place identity, and coordinated investment across housing, environmental assets, and community amenities. These elements are not simply matters of liveability but are central to overcoming development risk, enhancing market confidence, and addressing the temporal misalignment between infrastructure delivery and housing construction that frequently undermines large-scale projects. Their significance reflects the broader reality that housing provision is shaped by institutional capacity, financial risk allocation, and governance coordination as much as by land availability. Against this backdrop, the PBS is a response to the structural and institutional limitations of existing housing development delivery frameworks. Rather than treating housing as a discrete output serving those delivering it, the approach recognises housing development as a socio-spatial process requiring coordinated governance, infrastructure alignment, well-being and long-term stewardship.

4. Built Environment’s Track Record with Innovation and Improvement Agendas

A critical starting point for understanding the challenges the PBS may face resides in recognising the deep-seated institutional antecedents that shape the conditions under which it is played out. The built environment sector does not constitute a malleable blank canvas; rather, it is characterised by institutional logics, governance structures, and evaluative frameworks that actively constrain the trajectories along which innovations are able to travel. This is, in part, a core element of the research problematic evidenced by the sector’s longstanding relationship with innovation framed through a discourse that is predominantly reductionist, negative and ultimately counterproductive. For decades, government departments, QUANGOs, consultancy bodies, and sections of academia have produced successive improvement reports that recycle familiar recommendations without offering substantively new insights. These are embedded within a paradigm that privileges efficiency over effectiveness often treating context as either peripheral or a separate external variable. Such reports reduce complex socio-technical systems to narrowly defined performance metrics resulting in uptake and scaling changes.

This pattern of engagement with innovation has entrenched a powerful narrative that casts the sector as inherently resistant to change, thereby shaping expectations and causes. Such a narrative is analytically limiting and obscures the structural mechanisms through which innovation attempts are evaluated, translated, or dismissed. While the built environment sector does innovate, these innovations are frequently rendered invisible or marginal by institutional frameworks that are theoretically narrow, methodologically restrictive, and inattentive to the contextual contingencies that govern practice. Historically grounded analyses, such as those of Murray and Langford [17], reveal that persistent critiques of the sector stem less from an absence of innovation than from systematic misreadings of the institutional and sociotechnical complexity within which innovation unfolds. More recent work by Green [18] advances this line of critique by foregrounding structure, power, and organisational agency, offering a credible foundation for understanding how meaningful transformation might be conceptualised and innovation uptake is enacted.

When considered through the lens of uptake and scaling, these institutional dynamics become especially consequential. Innovations such as the PBS must navigate a regime configured to maintain stability, protect established interests, and reproduce existing development logics. Institutionalised routines, entrenched professional norms, risk-averse investment practices, and regulatory frameworks collectively shape the interpretive and operational space within which innovations are received and made sense of. These dynamics not only filter what is considered appropriate or feasible but also delimit the capacity of transformative approaches to gain legitimacy, mobilise actors, and persist long enough to influence regime-level reconfiguration, adverse investment practices, and regulatory frameworks collectively shape the interpretive and operational space within which innovations are received. Thus, confronting the institutional constraints that influence the PBS prospects for wider uptake and scaling is the aim. The challenge is not simply to design a compelling alternative to that offered by the national house builders but to identify how such an alternative can traverse and navigate a system configured to resist the very forms of change it proposes. By situating these institutional barriers at the heart of the analysis, the groundwork is laid for a more substantive examination of the conditions; political, organisational, cultural, and structural that must be transformed if uptake and scaling is to occur.

This historical pattern of the built environment provides an important cautionary backdrop when considering the uptake and scaling of the PBS. Unlike prescriptive improvement agendas, the PBS is not a technical fix but a paradigm shift in how sustainable housing development and place-building can be conceived and enacted. However, recognising it as an innovation foregrounds the centrality of uptake and scaling challenges. Its successful uptake depends not on the persuasiveness of its principles alone but on its ability to navigate a sector shaped by entrenched institutional logics, path dependencies, and risk-averse governance structures. In this sense, the advocates of the PBS must acknowledge and strategically engage with the very factors that have historically undermined the uptake and scaling of other reform agendas. Understanding and addressing the institutional, organisational, and cultural barriers that condition uptake and scaling is therefore essential if the system is to transition from an innovative proposition to a widely embedded practice capable of reshaping the development regime.

5. Introducing the Place Building System (PBS)

Building on the preceding discussion, there is increasing recognition that effective place-making extends beyond physical design to encompass social, economic, environmental, and health-related dimensions [19,20,21,22,23,24,25]. In this sense, place can be understood not as a collection of individual components, but as an interconnected system, where spatial form, community life, and sustainability outcomes interact and reinforce one another (for e.g. where walkability supports both health outcomes and local economic activity).

To capture this multidimensionality, the PBS is introduced as the bounded innovation in this research. The PBS is not a singular intervention, but an integrated system architecture designed to support the delivery of place-based development [2]. It seeks to move beyond fragmented approaches to housing development by aligning spatial design, community life, infrastructure, and long-term sustainability within a coherent framework. Importantly, place is not only defined by its physical attributes, but by how it is experienced. Vogl highlights the importance of belonging as a key dimension in shaping this experience, drawing attention to the relational and lived aspects of place [26].

To operationalise this, the PBS brings together four interdependent benefits: health and wellbeing, economic value, environmental sustainability, and social cohesion. These dimensions represent key pathways through which places generate value for individuals and communities, shaping both everyday experience and long-term outcomes. Importantly, they are not treated as discrete components, but as mutually reinforcing dimensions, where outcomes in one domain influence and support others [27,28,29]. This integrated logic forms the conceptual ‘hub’ of the system.

Supporting this core is a broader delivery structure (illustrated conceptually through a hub-and-spoke model in Figure 1 below), which connects these principles as mechanisms of implementation [2]. These include knowledge exchange, stakeholder collaboration, and enabling processes that allow the system to be interpreted and applied across different contexts. In practice, this means the PBS is not a fixed blueprint, but a flexible and evolving framework, subject to interpretation by different actors and shaped by local conditions [24,25,30,31]. It is important to emphasise that the PBS is not presented here as a fully prescribed solution, nor is its internal composition the primary focus of this research. Rather, it is treated as a niche innovation within the housing development sector, whose significance resides in its potential to challenge and reconfigure dominant delivery logics of housing development in the UK. As such, the analytical focus of this research is not on refining the PBS, but on understanding how it may gain traction, scale, and influence the broader socio-technical regime within which it operates.

6. Theoretical Touchpoints

Successful uptake and scaling of any innovation is rarely determined solely by how ‘good’ the innovation is in objective, technical, social or ethical terms. For example, the PBS may outperform many current housebuilding models on paper across sustainability, community wellbeing, financial viability and long-term value but superiority alone does not guarantee uptake. Innovations succeed when they align with wider currents of thought, institutional interests and sectoral agendas. In the context of place-building, this innovation enters a competitive landscape where multiple actors are simultaneously attempting to define and shape what better development looks like.

Prominent among these include the Global Centre on Healthcare and Urbanisation (Oxford) and the multi-university TRUDD collaboration, both positioning health as the central organising principle for addressing the structural drivers of urban developments. Such initiatives, like the PBS, seek to nudge or even disrupt the current dominant rhetoric around units delivered. Each competes for legitimacy, attention whilst aiming to influence how practitioners, policymakers and investors imagine and enact improved approaches to place-making.

For any of the innovative approaches mentioned above to gain traction, thinking must move beyond reductionist and technologically deterministic assumptions about how change occurs. Decades of research on innovation uptake consistently show that diffusion is not linear, rational or automatic. From the foundational work of Trist and Bamforth [32] and Trist’s later socio-technical systems work [33], through to Rogers [34], Nelson and Winter [35], and culminating in the longitudinal studies of Van de Ven et al. [36], these studies demonstrate that innovations evolve over time through complex, often unpredictable interactions between ideas, institutions and actors.

Therefore, the PBS will interact with a fragmented sector marked by deep institutionalisation, established routines and multiple forms of structural lock-in. Many stakeholders remain bound (locked-in) practically, contractually and culturally to existing models of housing development in terms of procurement, risk management, subcontracting and delivery. This lock-in shapes how a new approach is perceived, the amount of associated disruption or change sought and the extent to which it can be meaningfully enacted.

Furthermore, innovation uptake is not a one-way journey, but an iterative process involving interpretive flexibility, stabilisation and then over time reconfiguration [37]. As different actors engage with the PBS in practice, they will interpret it through their own interests, constraints and local contexts. This means the PBS will inevitably manifest differently across organisations and regions. Periods of temporary stabilisation will occur whereby closure appears to have taken place where consensus forms around what the innovation is yet will, over time, be followed by renewed cycles of adaptation as new pressures, opportunities or stakeholder agendas emerge.

In this sense, innovation is ongoing, aligned with a becoming ontological perspective where change is understood as continuous and emergent rather than episodic [38]. Currently, the PBS has reached an initial point of stabilisation through its collaborative development phase (documented in [2]), but that is only the first step. As uptake and scaling unfold, those responsible for stewarding the PBS must remain actively engaged with its evolution, supporting constructive reinterpretation while safeguarding core principles.

7. Transitions Through Multi-Level Perspectives

A substantial body of theoretical work has attempted to explain how innovations achieve uptake, though many of these models offer little connection to reality, others are both more representative whilst also analytically robust. Frameworks concerned specifically with transitions are particularly pertinent, providing retrospective explanations of how uptake has occurred in practice and, in doing so, offer a valuable conceptual anchor. Such frameworks are especially salient given the deeply institutionalised and structurally embedded constraints within the built environment and housing development sector.

Transitions frameworks, most notably Geels’ Multi-Level Perspective (MLP) [4], have been developed and mobilised to explain how societies and industries have historically shifted from one stabilised configuration to another through the emergence and consolidation of innovations. Crucially, these accounts of such transitions emphasise that change did not occur through technological substitution alone; rather, transition unfolds through complex, long-term reconfigurations of markets, infrastructures, regulatory regimes, cultural meanings, and actor networks [4,39,40,41].

A relevant example of such a transition for the built environment relates to the largest ‘retrofit’ project ever delivered, long before the term retrofit was even coined by today’s commentators. That is evidenced by the replacement in England of domestic gas lighting with the domestic electric lighting we experience today. This country wide ‘retrofit’ entailed the restructuring of urban utility systems, professional standards, safety regulations, and user expectations ultimately displacing a deeply entrenched socio-technical regime.

Such historical cases demonstrate that sector-wide transformations of the scale sought by the PBS are neither unprecedented nor implausible. On the contrary, they can happen and have happened. Such examples counter the narratives mobilised by detractors that “the whole industry cannot be changed” by illustrating such transitions have indeed occurred, often in contexts where systemic inertia appeared insurmountable at the time. The value of these frameworks, therefore, resides in the ability to illuminate the mechanisms through which profound transitions become possible, and to guide our understanding of the conditions under which uptake and scaling may unfold. Again, the frameworks in question fall under the broad term transitions framework (across niche, regime and landscape-levels), being both a theory and a framework, and are aligned with socio-technical system (STS) transitions [4]. The transitions framework looks across three interconnected levels:

• Niche level innovators - This is where new solutions start, where they are born. They’re often small-scale, experimental, outside current or accepted logics and supported by dedicated communities or early adopters. Think of it as the “innovation lab” stage.
• Socio-Technical Regimes - These are the established systems, practices, and rules that dominate today (e.g. in our case the housing development sector. They tend to resist change because they are built for stability and efficiency.
• Landscape Pressures - This relates to the broader societal constructs, government policy, financial heading winds, conflict, geopolitical landscape and so on. These are arguably the most stable level of the framework.

The PBS faces a very real and often underestimated challenge of how uptake and scaling of the system might unfold. With the built environment sector littered with improvement agendas and initiatives that often fail to gain traction or realise their potential, consideration of uptake and scaling is vital. Whilst critique of the creation process of the PBS has previously been published [2], it is uptake, scaling and sector transformation that is the focus here.

To briefly unpack this, a contemporary illustration that most can relate to can be seen in the trajectory of video conferencing technologies. Although the core technologies had existed for years, they remained peripheral and very niche, failing to influence dominant organisational practices at regime-level. Only when the COVID-19 pandemic shocked the landscape-level, destabilising the prevailing business regime was large scale uptake possible. The regime became destabilised, creating the conditions for normalisation of digitally mediated work and a restructuring of the regime. This transition was uneven; some video conferencing platforms successfully moving from niche to restructure the regime, while others did not. Importantly, the shift demonstrated that innovation was not absent but constrained until external pressures landscape pressure rendered regime destabilisation and transformation unavoidable.

8. Transitions Toward a More Sustainable Housing Development Sector—MLP as a Sense Making Framework

The discussion now turns to how the MLP transitions framework might explain how the housing development sector could transition to something more sustainable, beyond the metric of units and more aligned with healthy place-making.

Currently, the PBS resides in what is described as the ‘niche’ level, the bottom right corner of Figure 2. The PBS is represented by the green hub with 10 spokes again. As discussed, the PBS is not the only innovation occupying the niche space that is looking to offer alternatives to the housing development sector. In essence, the PBS has competition within the niche, with different stakeholders and interest groups looking into how to better deliver housing development for future generations. Such competition comes from a range of directions as mentioned earlier and alsocommunity led style projects supported by the likes of the Joseph Rowntree Trust. These competing niche innovations are also represented here (Figure 2) as the swirling ‘green shoots of innovation’, bouncing off one another, all outside the norm, all on the periphery, all potentially pushing and challenging what might be done. In part it is the innovations within the niche that ‘gain traction’ or ‘get swept up’ (for reasons outlined shortly) that will eventually go on to begin to challenge the regime (although that is not the end of the story). Innovations that do not get swept up will fall by the wayside or more likely remain niche, perhaps regaining momentum as times change and new opportunities emerge. Yet, residing in the niche will not bring about the desired impact sought, instead the PBS would remain on the periphery of the sector, an outlier, a niche.

At the time of writing the PBS resides as a ‘niche’ innovation, with competition. It does not fit the current ‘regime’, is not part of the current regime, yet it is searching for (or rather it’s human supporters are searching for) legitimacy. The challenge going forwards seems to be enabling the PBS to move from being a niche innovation that is competing for a voice, to one that is heard, to gaining that all-important traction and moving upwards toward the regime.

However, the regime-level is robust, the housing development regime is stable and therefore very difficult to enter. The regime stability could be interpreted as what are often described as barriers to entry, a desire and ability to defend itself from possible innovation that might seek to change it. The PBS is such an innovation and thus faces a particular reality. The regime-level illustrated in red within Figure 2 is defined by stability. The national housing development sector is such a regime. It has a certain organisational structure and shape, established practices and narratives, key stakeholders with agency, interests and agendas. As a regime the national housing development sector is ‘locked-in’ to particular structural practices developed over many years. It is a complex socio-technical system and has close ties with UK Government. Interests and agendas create barriers to change and barriers to entry. In the example in Figure 2 the regime on the left side (labelled before the PBS) depicts today, with the regime of the national housing development sector holding a certain structure. That structure would be recognised by those stakeholders operating in or close to the national housing development sector. The regime structure and stability makes it almost impossible for the PBS to infiltrate or penetrate, yet under the right circumstances infiltration may occur.

Figure 2 also represents the agency associated with the landscape-level, shown in purple. The landscape is the most stable of all the levels, the very fabric of society. In many ways the landscape supports the regime. Notwithstanding this, occasional sudden shocks or unforeseen events can occur at the landscape-level. These shocks create aftershocks or ripples across the system, initially destabilising the regime. More specific pressures might come from recent policy developments, including the New Towns Taskforce report to Government [15], or more generically from global financial markets, conflict, energy pressures or natural disasters.

The aftershocks or ripples coming from landscape-level can and do ‘destabilised’ the regime. It is this destabilisation that many of the niche innovations have in effect been waiting for, for those at niche level destabilisation equal ‘the opportunity’. The destabilisation of the regime generates ‘the opportunity’ for both the regime and for any niche level innovation (the PBS). Innovations (rather, human actors acting on their behalf) that are perhaps best able to respond to the nature of the opportunity will perhaps mobilise the most traction toward the regime or rather the regime will seek to pull them in. Positioning destabilisation as an opportunity is perhaps not how all of those already established within the regime may perceive it. Alternative narratives around threats could be more representative. Yet for the innovators in the niche level (the PBS) this is certainly an opportunity because, whilst the regime is destabilised, perhaps re-calibrating, re-setting or re-structuring in response to the shock landscape event it will look toward the niche innovations, perhaps supporting some to rise up, infiltrate and shape that re-structuring. This is represented through the turbulence in the centre (Figure 2), where disruption, new agendas, instability and opportunity are shown.

Over time, it is envisaged that the regime will be ‘restructured’. The regime of the national housing development sector. This occurs not only in response to the landscape shock, but to accommodate the innovation, with the innovation becoming part of the very fabric of the newly restructured regime. The structural make up and shape of the regime as it slowly returns to a degree of stability will look different, potentially now including the PBS (as illustrated on the right side of Figure 2, the regime-level labelled regime after PBS). This informs and shapes our thinking in terms of the recent, current or possible emerging landscape pressures, shocks or possible events (financial, energy, policy, white papers, taskforce guidance, conflict, regulation) that have or may destabilise the national housing development regime in the UK and the levers that could be purposefully activated to instigate uptake and scaling.