Tacit domains: The transference of practitioner know‐how in contemporary English planning practice

This article reflects upon ideas of tacit knowledge in order to examine the nature of planners’ expertise. It investigates the shifting knowledge and power dynamics between and within the public and private sectors, as a means of determining how tacit expertise is transferred and re-appropriated in new domains and geographies of practice. Tacit understanding of what facilitates successful permissions and what impedes the approval process, helps planners navigate the plan-led system and avoid inertia. Findings are two-fold. Firstly, public sector planners transfer their own expert tacit knowledge to influence and direct local development planning. Secondly, the findings illustrate that public sector planners feel their tacit expertise is increasingly undervalued and traditional networks of knowledge transference have been dismantled due to the erosion of networks of peer support. This results in a disruptive counter narrative based in private planning practice where public sector experts are re-emerging in commercial practice due to a range of factors, including: budgets cuts; demoralisation; and seeking greater job security in the private sector. This leads to new geographies of tacit knowledge, as local government planners transfer their knowledge into new professional environments. This can result in reconfigurations of locally embedded A cc ep te d A rt ic le


Introduction and methodology
The aim of this article is to reflect upon ideas of tacit knowledge in order to examine the nature of planner's expertise. It investigates the shifting knowledge and power dynamics between and within the public and private sectorsas a means of understanding how tacit expertise is transferred and re-appropriated in new domains and geographies of practice. As local planners move to new local authorities in different locations or join private consultancies, that have wider geographical remits. This focus is important because this transference has the potential to restructure the persistently local planning process through a new politics of expertise. However, it also has the opportunity to deterritorialize traditionally local knowledge and reposition it in different contexts beyond its original zone of creationcreating a new, more diffuse, geographical assemblage of planning knowledge. The article addresses the overall research aim with two underlying research questions: (1) What is the value of local government tacit knowledge in contemporary planning practice?
(2) How is local government tacit planning knowledge valued, transferred and reconfigured in new domains of practice?
The empirical material in this article is based on 20 semi-structured elite interviews (Temonos and McCann, 2013) investigating the issue of tacit knowledge and the trajectory of its diffusion between domains. The research was conducted during 2017 with planning practitioners operating in senior positions within both the public (70%) and private sector (30%). The authors initially targeted senior planners and then used a snowball approach to expand the sample through local authority and Royal Town Planning Institute (RTPI) networks. Although a relatively small sample, this methodological approach generated a unique sample of responses from experienced practitioners across a comprehensive geography. The authors intentionally avoided Freedom of Information requests because of Accepted Article the likelihood of legalistic and sanitised responses, which are unlikely to reflect uncodified tacit knowledge. Whilst, there is clearly an imbalance in numbers between public and private side planning, the aim of the research is to understand the transference of planning knowledge into private practice. All of the respondents were senior professionals with enough experience and seniority to provide an overview of the movement of knowledge between both domains. A minimum of two respondents were targeted in each of the eight former standard planning regions in England, to provide balanced geographic coverage. All respondents had in excess of 15 years' experience in planning roles, either development management, strategic planning and/or consultancy. The majority of the interviews were conducted face to face, a small number were conducted via telephone, and all were recorded, transcribed and then coded using an analysis matrix. A selection of quotes are utilised within the latter half of the paper to elucidate key themes from these practitioners.
The remainder of the article considers the academic context for the research and sets out a conceptual framework for the article. It then analyses the empirical material and discusses the major findings before reflecting upon the underlying research questions and contemplating their implications for the evolution of planning theory and practice. The overall conclusion is that conditions of austerity and changing governmental ideology has led to an evolving knowledge power dynamic that has the potential to disrupt and reconfigure the collaborative power relations underpinning local planning practice in England.

Literature review
Within urban planning, the expertise of the professional masterplanners and the all-seeing gaze of unitary planning regimes has been contested for decades (Sager, 1994). For example, building on relational concepts of space and place (Massey, 2005) and communicative action (Habermas, 1981) the traditional role of the expert planner was destabilised through the communicative planning turn (Healey, 1992;Innes and Booher, 2002). This placed collaborative planning, and through critical debate, multi-scalar geometries of power, networks of activity and contested decision-making and outcomes (Tewdwr-Jones and Allmendinger, 1998;Innes and Booher, 2014) at the centre of what came to be known as collaborative, communicative and post-positivistic planning.
However, within academia there has been less emphasis upon the mobility, structuring influence and emerging geographies of planning knowledge. Although, it must be noted that there is some evidence of research in the knowledge expansion domain (Perl and White, 2002), regulatory capitalism (Levi-Faur, 2009;Raco, 2014) and the politics of planning expertise (Linovski, 2016). Nonetheless, analysis of how planning knowledge is acquired, developed and mobilised within and between organisations and how this then influences Accepted Article local planning policy is less frequent. Therefore, rather than focusing on the sanctity of knowledge and expertise per se, or the relatively well researched geographies of policy mobility (Peck and Theodore, 2015) the authors focus on the generation, transference and mobility of planning knowledge into new domains. In this case, from the public to the private sector consultancy planning domain.
In doing so, the paper contributes to the arguments of Dear (1989) in relation to the privatization of planning practice, Steele (2009)  Initially, the authors approach this knowledge transfer through the work of Polanyi (1958) into codified and tacit knowledge. They then utilise the contemporary work of Lundvall and Johnson (1994), Zook (2004), Fischler (2000) and Hacking and Flynn (2017) who expand Polanyi's simple dichotomy into a more complex typology connected to shifting networks of influence and the consequent politics of knowledge and power. The authors adopt this approach in order to understand how relatively stable notions of collaborative planning at the local scale -traditionally facilitated by public sector planners, are being destabilised and transformed into new organisational and geographical assemblages' when local government planners move into new domains of influence in private consultancy. Polanyi (1958) introduced the idea of tacit knowledge, arguing that we can know more than we can tell. His assertion was that expertise is deeply personal and difficult to communicate verbally or in writing and was more reliant on intuition. Tacit knowledge has been described as "know-how" as opposed to "know-that" (facts). In this sense, there is no distinction between expert knowledge and tacit knowledge as both are interconnected. Lundvall and Johnson (2004) and Zook (2004) expanded Polanyi's dichotomy in the following way:

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 Knowwhat (broad knowledge about facts which is similar to information)  Knowwhy (an understanding of scientific principles)  Knowhow (context specific expertise)  Knowwho (the density and strength of social networks) This latter treatment of tacit knowledge forms the conceptual framework for this article. The first two categories are analogous to Polanyi's (1958) explicit fact based knowledge while the latter categories relate to implicit tacit knowledgeits context specific base and the importance of networks in transferring and reconfiguring tacit knowledge.
In this article, tacit knowledge (often generated over decades) helps planners, and their communities of practice, influence and mediate within the development process. During their careers, planners accumulate expert tacit knowledge in relation to their material local domains and institutional practice. However, this facilitating role is also one of privilege, giving local government planners access to uncodified knowledge, or to use Beauregard's (2004) terminology, 'thick' understanding of individual places. Illustrating this situation, subsequent sections of this article will argue that once generated, this knowledge can be mobilised and transferred into new place-based assemblages of knowledge and expertise depending on the eventual domain of the planner (e.g. between public and private).
As planners are vital stakeholders in the development process, their deep knowledge of local areas can be a desirable asset for private sector planning consultancies. This is not a new phenomenon, public sector planners have moved into private practice for decades and vice versa. This process has enriched the planning discipline through a fluid circulation of ideas.
However, there are signs of an accelerated unidirectional movement, from local government planning into private practices. The Royal Town Planning Institute (2019) noted that while the total number of planners in England has grown slightly since 2010. There has been a decrease in the percentage of (all) planners being employed in the public sector from 70 per cent in 2006 to 56 per cent in 2018 (Edgar, 2019). This generates potential for a tacit deficit in local government planning and the loss of decades of knowledge. This repositioning of knowledge and power within contemporary planning practice forms the interrogative context for the empirical material in the remainder of this article.
The English plan-led system requires developers to submit a planning application, which is then assessed via discretionary scrutiny at the local level based on individual consideration of site-specific material planning considerations. Consequently, in the English context; tacit knowledge of how the local plan has been developed; what the implicit meanings are within the text of the plan; and, how much latitude planners allow in considering 'local

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This article is protected by copyright. All rights reserved circumstances' is valuable to the private sector. This tacit knowledge can lubricate the development management process, circumventing some of the uncertainty within the system. The proceeding section reflects on this situation in England. It considers how the development plan process is being reconfigured at the local scale, the role that knowledge plays in this negotiation and how planning knowledge is evolving and being repositioned in new locations. There was also a growing degree of ethical concern amongst public sector respondents, that, due to the importance of tacit knowledge being transmitted via networks, individuals could act as 'gatekeepers', as planners wield power through their unique understanding of local planning contexts. Ultimately, this raises the possibility of tacit knowledge being utilised

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This article is protected by copyright. All rights reserved in a negative sense to circumvent the wishes of the local community and force through development. In this case, the gatekeeper can be seen to have potential market advantage.
However, even private sector respondents reported greater concern with the ethics of this situation rather than the commercial benefits for the private organisation.
Despite respondents viewing tacit knowledge as significant in the planning process respondents within the public sector, emphasised that 'knowledge' was not a match for private sector 'financial muscle'. This asymmetrical power dynamic has become more This substantiates Lord and Twedwr-Jones (2018) assertion of a co-ordinated neo-liberal ideological push to deregulate planning. The injection of levers of policy centralisation and deregulation have co-existed with a period of stigmatising planners as obstructive bureaucrats. Coupled with austerity cuts this has led to one third of local government planners in England leaving the public sector (RTPI, 2015). In the proceeding sections, the authors outline that some local government planners have moved into private sector consultancy in search of new careers. In this evolving environment, gatekeepers of local knowledge now combine with 'financial muscle' and can seek to manipulate, and in some instances circumvent, the local planning process on behalf of private interests.

Transferring knowledge: how is local government tacit planning knowledge valued, transferred and reconfigured in new domains of practice?
Public sector planners have been vilified by national politicians (Lord and Twedwr-Jones, 2018), starved of financial resources and placed under increasing demands. Subsequently, for many demoralised practitioners the temptation to leave the public sector has become irresistible, There is a perception that the more able planners have joined consultancies...the less able stayed… and are deeply demoralised. The direct consequence of this is that inexperienced local government planners can be pitted against adversaries who possess an unrivalled knowledge of the local plan and the wider evidence base that the LPA are attempting to defend. This implies a rescaling of the power dynamics within the politics of local planning. Influenced by the transference of tacit knowledge into new domains and utilised for divergent aims to those originally envisioned during co-creation with local stakeholders (e.g. the public good).
The NPPF is widely viewed as a 'developer's charter' which has undermined LPAs negotiating position against developers. Developers frequently commission planning consultancies to navigate the planning system and to provide a 'solutionist' approach to challenges in the system (Parker et al, 2018). Whilst a number of respondents from the public sector reported that colleagues had recently left the public sector, to join private sector consultancies, no respondents from the private sector reported colleagues heading to the public sector. A small number of former LPA planners indicated that they subsequently used their expert knowledge of weaknesses in objectively assessed local housing need to bolster Accepted Article developer's cases when applying for controversial housing sites. This ties in with Parker et al's (2018, p737) findings, of an '…opening up of the planning process to inputs from a range of private companies who are adept at selling their ability to offer 'solutions' to specific issues as set out within the system'. This point is important because the weaknesses in local planning are often hidden, context specific and only known to those with local knowledge.
Our respondents were very reluctant to identify specific cases, where 'insider' knowledge had proved crucial but it was acknowledged throughout the study as an issue in the planning system.
After a decade of austerity the consequent erosion of public sector planning teams cannot be understated. Public sector respondents noted growing time and resource constraints, increasing volumes of work, lack of specialist skills and stretching government targets'.
Responses which align with Raco's (2019) analysis which highlights professional planning bodies reporting low morale, overwork and lack of resources amongst public sector planners. Cumulatively these issues have significantly affected the opportunity for remaining staff to engage in networking, training and knowledge transfer. Restricting opportunities for staff development, internally through mentoring from experienced colleagues (who have often left the system) or via external networking.
We have lost some 'wise old heads' due to redundancy, early retirement and people simply deciding that have had enough…, that level of knowledge is very hard to replace.
(LPA Planner, Core City, Midlands) This implies place-based structures of knowledge are being disrupted and potentially eroded as planner's move from the public to the private sector. Concurrently, knowledge originally generated at the local scale has the potential to be re-purposed and employed in new locations as private sector planners often work over wider geographies.
All respondents in this study revealed a growing process of public sector planners moving into the private sector and subsequently influencing the local planning process on behalf of developers. However, in the papers distinct focus on knowledge transfer to private sector consultancy it is worth noting that, the public-private binary is not static nor is it always oneway. Steele's (2009) seminal working in an Australia context introduces the potential for a 'third space' in planning between the public and private sector, via a form of hybridised planning. Parker et al (2018) have recently illustrated the fragmentary nature of contemporary planning practice with some LPAs buying in specialist planning skills from the private sector. Our research did not find significant evidence of a widespread evolution of hybrid planning across England. A limited number of local authorities are outsourcing their Accepted Article statutory planning role and associated staff into private companies. Under this arrangement, planning staff 'TUPE 3 ' transfer into private employment in order to deliver their previous public sector roles, providing an evolving example of the hybrid planner depicted by Steele (2009). A minority of organisations are also specifically positioning themselves to take on exclusively public sector contracts to avoid conflicts of interest (see for example the not for profit Public Practice social enterprise organisation in the UK who position professionals in the public sector). However, our research indicated a different side to the hybridity argument which has, hitherto, mostly focused on private companies carrying out work for LPAs and a certain coming together between public and private. Instead, our research indicates a movement of tacit knowledge away from LPAs into private consultancy. This does not necessarily reflect hybridity, rather a re-assemblage of previously constructed knowledge.

Conclusion
In response to the first research question -what is the value of tacit knowledge in contemporary planning practice? The findings in this article indicate that tacit knowledge is a coveted planning resource. However, it is also one that is privileged and imbued with significant latent power, depending on the context in which this resource is operationalised.
The practical implication for local government planning practice is that there is now an emerging deficit in knowledge and expertise in local government planning as the public sector faces serious challenges in terms of recruitment and retention of planning talents (Hills, 2019). In response to the second research question -How is local government tacit planning knowledge valued, transferred and reconfigured in new domains of practice?
Relatively stable roles in the planning process, played by local government planners, are changing due to knowledge movements -for example, from local government to private consultancy during a sustained period of austerity and local government downsizing. The tacit knowledge built up through decades of local planning practicebroadly associated with local development plans, is being re-employed by planning consultancies and then reappropriated to advise on this same documentation. This suggests a shifting knowledge power dynamic that has the potential to influence and potentially redefine some local planning decisions.
Moreover, it is important to note that it is not just the individual planner and their individual knowledge, that moves into another domain, they also take the collaborative knowledge built up within a community of practice, with them. This represents a new knowledge/power dynamic, which has repositioned collaborative knowledge and exposed a challenging ethical question within the dynamics of local planning practice. This suggests an evolving planning landscape where many of the positive aspects of local communicative action and stakeholder contribution should be questioned and re-examined under new circumstances of knowledge status.
In considering these questions, the paper highlights the new contingencies and movements that are re-shaping notions of knowledge and expertise in the planning discipline (Raco et al, 2016;Linovski, 2018). In contrast to the recent focus on hybrid relations between public and private planning (Steele, 2009), the paper finds instead separation between and knowledge transfer from public to private domains. Instead of hybridity, the paper posits new assemblages of planning knowledgeas planners reposition themselves in the local planning process and, potentially, uproot collaborative knowledge into new domains. It also sheds new light on how the relative use and position of expert knowledge affects goal achievement in planning development and local place (Tennoy et al, 2016) and provokes questions around the original generation of place-based planning knowledge and consequent trust (Parker et al, 2014).
Local government planners are not only moving into private sector consultancy, others are retiring, moving into academia or leaving planning completely. In these cases, valuable tacit knowledge is lost. The authors focus primarily on the privatisation of public planning knowledge into planning consultancies. However, this almost certainly over simplifies the situation. A simple binary between public and private does not exist. For example, there are clearly examples of a hybrid 'third space' in planning practice occupied by private outsourcing organisations delivering public services and fulfilling regulatory responsibilities.
In an era of austerity, this is a pragmatic decision, safeguarding expensive planning knowledge in long-term contractual situations. In addition, not all private sector employers will be representing private sector interests. For example, private sector consultancies do viability assessments of local plans for both public and private clients and complete specialist task like heritage appraisals for LPAs. Indeed, there is potential for some consultancies to position themselves so they only take on public sector commissions in order to avoid any potential conflicts of interest.
Both of these issues offer considerable potential for further research into tacit knowledge, its multi-scalar creation, transfer and use in new local assemblages within an evolving planning landscape. Hybrid systems which employ outsourcing approaches reveal a largely unresearched complexity associated with top-down corporate ownership and use of this previously held public knowledge and expertise. An interesting line of enquiry would be to consider how much of the recent shift into private sector planning employment (outlined by Accepted Article