Planning matters

The roll-out of strategic planning has started, reflecting the last Government’s intention that there would be England-wide coverage by the end of this Parliament, expected to be in Summer 2029. Strategic planning will be via spatial development strategies (SDS), albeit there is a current consultation on Mayors having development management powers ahead of an SDS being published.

The legislative basis for SDSs and the bodies that prepare them is in the Planning and Infrastructure Act 2025 and the English Devolution and Community Empowerment Act 2026.

Bethan Haynes explained the intention and challenges for SDSs, including how they are administered, and reflected on the (then) Planning and Infrastructure Bill requirements, in her blog of March 2025. A follow up to that blog - ‘Big plan theory’, considered the progress made. Ed, Dom and Sean considered changes to the then English Devolution and Community Empowerment Bill as it had progressed through the Houses. This included the priorities of an SDS’ strategic planning policies, for example that an SDS “must prioritise development on brownfield land and urban densification it must also seek to increase sustainability and community building by minimising the distance of travel between residential and commercial areas”.

Beyond the legislation, the National Planning Policy Framework (NPPF)[1] sets out the national policy for plan-making, including 17 specific plan-making policies. This blog focuses on those policies.

The NPPF also defines spatial development strategy in its glossary at Annex A:

“Spatial development strategy: A plan containing policies on the development and use of land on matters of strategic importance to the area prepared by strategic planning authorities and the Mayor of London”.

National plan-making policies

The NPPF’s introduction explains that there is some interpretation needed when applying national policy to Spatial Development Strategies (SDS) “where policies relate to matters that are primarily local in scale, and/or are concerned with detailed implementation, they will not generally apply to spatial development strategies”.

It also reminds of an important point when considering the role of SDS in the development plan: “The relevant legislation does not allow spatial development strategies to allocate specific sites or designate specific areas of land”.

The NPPF also explains how SDS should be prepared and examined. 

PM1: Spatial development strategies

Policy PM1 is the overarching national policy regarding the preparation of SDS.

“[An SDS should] set a positive vision for future growth and change at a sub-regional scale and provide a clear spatial framework for investment and growth, including for new housing”

Setting out the aims of an SDS, the NPPF is clear that its “Content should be genuinely strategic in nature”. Parliamentary debates during the passage of SDS related legislation made clear that the last Government and other politicians were keen to avoid strategic plans to be published with the length or detail of the London Plan. The current Government has continued to seek to design the system to avoid  unnecessary policy duplication or complication, including the ‘layering’ of policies. More detailed or locally specific issues should go into local plans or be picked up through National Decision Making Policies[2] as “other parts of the development plan”.

The NPPF sets out nine ways in which this should be achieved, lettered a-i, which provides a list of minimum contents, evidence and analysis.

We review or provide a summary of each.

Plan period, monitoring and implementation - strategic means strategic

a. and b. set out timescales and the locations for growth that should be identified.

“a. Setting out a strategy for a sustainable pattern of growth covering a period of at least 25 years, including through the apportionment to local planning authorities in the strategy area of objectively assessed needs for housing and other uses that are best considered at a strategic scale for the duration of the plan period;”

And

“b. Identifying broad locations for growth and regeneration, including new settlements, major urban extensions, major cross-boundary development and other key locations with the potential for significant new homes, jobs and other development [which should extend over strategic site allocations in adopted plans]”;

The consultation document proposed a 20-year period. The Government has increased this to 25 years “To support long-term certainty for planning, infrastructure delivery and investment”, according to its response to the national policy consultation[3].

The 25 year period is a different timescale to the 10 years for which an LPA must consider housing needs.

The SDS period should be read with the monitoring and implementation policy for SDSs, set out at i. This says that commencing preparation of a replacement or altered version should happen no later than seven years after the current version was adopted, or earlier, if certain criteria are met. The criteria are essentially where either the strategic planning authority or Mayor of London consider the SDS inconsistent with national policy, or changes are planned to infrastructure that might affect delivery or to respond to new evidence that show significant changes to needs, opportunities or development constraints.

Setting strategic development locations will be a key priority for SDSs; the ability to plan over 25 years will allow for medium to large sites to be planned for in this way along with enabling infrastructure. However, our research on planning and development timelines has shown, that for the largest of sites for example new settlements, this time frame will remain challenging. 

Indeed, the current NPPF is clear that “Where larger scale developments such as new settlements or significant extensions to existing villages and towns form part of the strategy for the area, policies should be set within a vision that looks further ahead (at least 30 years), to take into account the likely timescale for delivery”. If, as directed by PM1, SDS should identify ‘broad locations’ for growth – which includes New Settlements – they will surely need to be looking ahead at least 30 years?

The interface of plan-making, between SDS and local plans, is explored in Matthew Spry’s recent blog Make more little Plans? The NPPF’s shift to ten-year local plan periods.

PM1 says SDSs should also be:

“c. Supporting economic growth by providing a spatial framework for strategic investments and giving spatial expression to strategic elements of Local Growth Plans and the Industrial Strategy[…];

d. Identifying the general extent of areas established as Green Belt and broad locations where changes to Green Belt boundaries may need to be considered through local plan preparation, if necessary to meet the development needs of the strategy area;

e. Identifying broad locations for nature conservation and habitat enhancement, restoration and creation; and addressing strategic issues relating to the protection and enhancement of the historic environment;

f. Setting out the type, extent and broad location of strategic infrastructure needed to enable development and serve existing communities […] [and make provision for certain committed infrastructure];

g. Using appropriate maps and diagrams to illustrate and communicate the strategy;

h. Providing a proportionate level of information on the mechanisms for delivering the strategy”

”[…];

The SDS will be expected to identify the broad locations for infrastructure investments, and other aspects (as above) with local plans covering the detail. The ‘general extent’ of Green Belt boundaries might be open to interpretation and will likely be contested locally in areas with Green Belt constraints, where the combined housing needs of an SDS area are high.

With regard to requirement g., appropriate maps and diagrams, policy S2(2) (Producing a spatial strategy) says:

“The spatial strategy should be illustrated on a key diagram forming part of a spatial development strategy and/or local plan (or minerals and waste plan, where relevant), with the boundaries of specific policy areas, land-use designations and allocations identified on a policies map”.

The policies map[4] is a map required by the new plan-making system, which identifies all the development plan allocations on an Ordnance Survey base. A spatial development strategy cannot allocate sites and so the key diagram will not be included on the policies map. The policies map allocations are the fine grained, follow up to the broad locations identified on the key diagram.

Vision and cross-boundary cooperation

The vision and spatial strategy of local plan should support the delivery of the spatial development strategy (PM2). Policy PM10 sets the approach to maintaining cooperation on cross-boundary matters and PM11 on demonstrating cooperation. The Government’s response to the national policy consultation says that PM10 and PM11 “support flexible and proportionate approach” and that guidance will also be published to support authorities in meeting those policies. Acknowledging the wide range of bodies that the need for cooperation applies to, the response also says, “The government will also continue to work with relevant government departments and infrastructure bodies to improve alignment between long-term infrastructure planning and development plan-making, including through wider infrastructure planning reforms”.

Relating back to that important interface between local plans and SDS, PM10(3) also states that:

“Where matters are already addressed by an adopted spatial development strategy, plan-making authorities within the strategy area do not need to revisit them when preparing their plans”.

The ‘matters already addressed’ referred to in the policy wording includes housing targets i.e. SDSs will be required to set out each constituent LPA’s housing need figures against which their local plans and housing delivery test measurements will be assessed.

PM10(4) refers to using ‘available information’ a term carried over from the superseded NPPF 2024:

“Where there is uncertainty about the future direction of other parts of the development plan or the plans of infrastructure providers, such as due to misaligned timings, plan-making authorities should make pragmatic decisions on the basis of available information rather than waiting for a full set of evidence from other bodies”.

This, in many areas, is likely to be crucial, given the potential lag between an SDS and a local plan being prepared, as it avoids the pitfall of the uncertainty of ‘unmet need’ numbers.

A potential challenge to this new system is how to deal with the unmet need in an SDS that cannot meet its own housing needs within its boundaries. For example, an urban combined authority that might have previously (under the duty to co-operate) shared need with neighbouring local authorities, that form part of the same housing market area but are now in a different SDS. Essentially, the challenge is how to deal with unmet need that remains at an SDS level across different SDS areas.

Positive plan-making

The plan-making policies within the chapter on achieving sustainable development and policy PM14 (Examining spatial development strategies), emphasise the need for positive plan-making. Policy S1 says that planning positively means providing for new development and environmental improvements in a way that promotes a sustainable pattern of growth and seeks to mitigate climate change and adapt to its effects. It also means “providing for objectively assessed needs for housing, business and other uses (including supporting infrastructure), as well as any needs that cannot be met within neighbouring areas, unless:

i)                    The application of the policies in this Framework that protect areas or assets of particular importance [FN24][5] provides a strong reason for restricting the overall scale, type or distribution of development in the plan area; or

ii)                  Any adverse impacts of doing so would substantially outweigh the benefits, when assessed against the policies in this Framework taken as a whole”.

Policy PM14 says that a sound SDS must satisfy tests of being “positive” and “appropriate”. With regard to the “positive” test, PM14(2)(a) says:

“The strategy sets out a positive approach to delivering growth which, as a minimum, seeks to meet the area’s objectively assessed needs, and is based on effective joint working on cross-boundary strategic matters. A strategy which does not provide for objectively assessed needs should be considered an exception, and only where it is evidenced that stringent efforts have been taken to meet those needs through cooperation with other strategic planning authorities”

The explicit reference to a need for the SDS to be positive is helpful, with the emphasis on these plans meeting their needs except when there is evidence “that stringent efforts have been taken to meet those needs”. Positive planning means “meeting the development needs of an area” is described as a minimum, for both SDSs and local plans.

Under this framework, an SDS becomes the basis for the level of development in an area (including as PM10 notes, housing need). SDS are considered to address both the duty to cooperate issues that arose in the last plan-making system and to address broader land supply challenges.

Other plan-making policies

Other national policies that guide SDS preparation and application include:

HO1/HO2 – SDS to assess the need for homes and establish a housing requirement

M1– SDS to assess the provision needed for aggregate and industrial minerals, where appropriate

GB2 – assess the strategic role of Green Belt land within the strategy area and identify where boundaries may require further consideration in local plans

TR1 – may set thresholds for what constitutes a significant amount of [transport] movement arising from new development,

Final thoughts

As noted in earlier Lichfields analysis, strategic planning has the potential to overcome some of the most significant barriers to development that we have seen over the last decade and to unlock a genuine solution to cross-boundary issues like infrastructure and housing. The ongoing challenge of local government reorganisation and strategic authorities will be key to ‘getting the geography right’ in some of the most politically sensitive areas, as well as the capacity and institution building necessary to get effective plans means that we are still a way off from universal coverage. Political crosswinds, economic challenges and the ongoing stasis in much of the economy will continue to challenge development in many areas. However, for the strategic authorities that are already in a position to start preparing their SDS, there is the potential to provide effective integrated strategic plans that reflect local needs and cover the next twenty five years of development. 

Work has started on several spatial development strategies outside of London, with more in the wings.  See Table 1 for our understanding of current progress.