Using evaluation to strengthen a whole-system approach to serious youth violence in Lambeth

Lambeth Council applied to the National Institute for Health and Care Research (NIHR) for an independent evaluation of Lambeth Made Safer, its ten-year public health and anti-racist strategy to reduce serious youth violence, via the NIHR Public Health Intervention Responsive Studies Teams (PHIRST) scheme. PHIRST South Bank were commissioned to deliver the evaluation, supported by Lambeth’s Health Determinants Research Collaboration (HDRC). Completed in 2025, the evaluation was designed to assess progress and strengthen learning, partnership working and delivery during a period of significant organisational change. This case study reflects on what Lambeth learned about using evaluation in a resource-constrained environment, the value of community voice and qualitative insight, and why evaluation is increasingly critical for councils tackling complex social challenges.

Serious youth violence (SYV) has wide-ranging consequences for health, wellbeing and opportunity. In Lambeth, SYV has long been understood as more than a policing issue -  it is shaped by structural inequality, trauma, and the wider determinants of health.

In 2020, Lambeth Council launched Lambeth Made Safer (LMS), a ten-year strategy grounded in public health and anti-racist principles. The strategy spans multiple workstreams and partners, including council services, the NHS, police, schools and voluntary, community, faith and social enterprise (VCFSE) organisations.

As the strategy developed, the Council recognised the need to understand how LMS was working in practice - how partnerships were functioning, how communities were experiencing interventions, and how learning could be used to strengthen delivery over time. Measuring outcomes alone was not sufficient for a strategy of this scale and complexity.

The Council wanted an evaluation that would:

• Understand the early development and implementation of a complex, whole-system strategy.
• Capture learning about partnership working, systems and context.
• Meaningfully include the perspectives of communities and young people affected by violence.
• Support learning and improvement during delivery, not only at the end
• Be useful in a fast-changing, resource-constrained local government environment.

Lambeth Council applied to the NIHR Public Health Interventions Responsive Studies Teams (PHIRST) call, to request an independent evaluation of the LMS strategy. The PHIRST scheme specialises in evaluating complex public health interventions in local authority settings.

The PHIRST South Bank team, based at London South Bank University, were assigned the project and delivered a process evaluation focusing on the development and early implementation of LMS (2018 to 2023). Lambeth HDRC played a key brokerage and support role throughout - translating local priorities into research questions, supporting collaboration between academic and council teams, and acting as a bridge between different organisational cultures and timescales.

From the outset, attention was given to getting people on board across a complex system. Early engagement focused on building a shared understanding of the purpose and value of a process evaluation, particularly among council teams and partners unfamiliar with this approach. This was achieved through co-production workshops, regular touchpoints with LMS stakeholders, and ongoing dialogue to align evaluation activity with operational realities and community priorities. Lambeth HDRC provided continuity and acted as an anchor during periods of organisational change.

Evaluation during organisational change

The evaluation took place during a period of significant change within Lambeth Council, including restructuring, staff turnover and wider pressures on public services. This context shaped both delivery and learning.

Having a dedicated research and evaluation function through HDRC proved critical. HDRC helped maintain continuity, relationships and institutional memory as teams and roles changed. Reflecting on the project, it became clear that without this function (or an equivalent), sustaining momentum and shared understanding would have been considerably more difficult.

One constant” in the context of change was the ongoing reality of residents’ lives and the conditions shaping risk:

So, knowing we are going to go through this change, the people in the borough and the lives in which they live, the socio-economic status of those people is not going to change – that’s the one constant.
 Local government staff

Senior buy-in and leadership

The evaluation highlighted the importance of sustained senior leadership sponsorship for the evaluation process itself, particularly within complex, long-term strategies. Although efforts were made to secure senior engagement at the outset, reflection suggests that buy-in to the evaluation could have been strengthened further and revisited more consistently throughout its lifespan.

Clarifying what a process evaluation is

A key learning was the challenge of setting expectations among stakeholders about what a process evaluation is and what it can offer. For some, evaluation was initially associated with performance management or judgement. Over time, the project demonstrated that process evaluation can support understanding of systems and relationships, identify barriers and enablers to delivery, and enable learning and adaptation while a programme is still live.

Why evaluation matters in constrained environments

A core learning and a key message for other councils is that evaluation becomes more important, not less, when resources are tight (although finding the time for it takes considerable commitment).

With rising demand and limited capacity, evaluation helps councils prioritise, reduce duplication and ensure that scarce resources are used where they can make the greatest difference. The evaluation supported a shift from focusing on activity metrics alone towards understanding impact, experience and value.

As one council stakeholder put it:

Despite having done programmes and projects, received funding and there are lessons learnt; so we’ve got good numbers but what impact does it really have on those individuals’ lives?
- Local government staff

Public health and anti-racist principles

Grounding the evaluation in public health and anti-racist principles helped ensure that the needs and perspectives of communities most impacted by violence were integrated throughout the work.

Stakeholders described the public health approach as looking beyond individual behaviour to the wider determinants shaping risk and opportunity:

The whole point of the public health environment is that you don’t then just focus on it being … You have to look at what their housing is like, what their conditions are like, are they engaged… It’s a much broader thing.
- Local government staff

The evaluation also found universal support for anti-racist principles, alongside a need to strengthen shared understanding of how they are defined and operationalised in practice:

…there was a kind of commitment to an anti-racist approach… but perhaps there hadn’t been a very explicit ironing out at that point about exactly that looks like, what that means and how it could be operationalised.
 - Local government staff

One of the clearest impacts of the evaluation has been a renewed focus on how success is measured across violence-reduction services. Building on the PHIRST findings, Lambeth is now strengthening success measurement across commissioned interventions by embedding richer and more consistent qualitative tools.

Oversight for this work will sit with the newly established Violence Reduction Unit and will be monitored through annual action plans under the Safer Lambeth Partnership. This reflects learning from the evaluation about the limits of relying on quantitative indicators alone.

The council will refine lived-experience measures, expand the use of structured case studies, and apply mixed-method approaches - including adapted surveys and structured narrative reporting - to better capture outcomes that matter to communities, such as trust, relationships and perceptions of safety.

Collaborative work between the Violence Reduction Unit and Lambeth HDRC will support the integration of these qualitative metrics alongside existing KPIs, ensuring a stronger focus on equity, learning and improvement within performance and accountability frameworks. A planned Violence Affecting Young People Experts-by-Experience Panel, which will be in operation during 2026-2027, will further embed lived insight into future service design and delivery, reinforcing the public health and anti-racist principles underpinning Lambeth Made Safer.

Valuing qualitative insight

Alongside changes to formal measurement frameworks, the evaluation also shifted how qualitative evidence is understood and used within the council.

The process evaluation demonstrated that lived experience, narrative and practitioner insight are not supplementary to quantitative data, but essential to understanding how complex strategies function in practice. For council teams, this helped build confidence in using case studies, stories and reflective accounts as legitimate evidence to inform decision-making - particularly in areas where outcomes such as trust, safety and relationships cannot be captured through metrics alone.

As one VCFSE partner reflected during the evaluation:

To recognise that case study would probably be more valuable than any number of numerical statistics.
- VCFSE representative

This learning is shaping how Lambeth approaches evaluation beyond Lambeth Made Safer, supporting a more balanced use of quantitative indicators and qualitative insight.

Creative dissemination

Creative approaches to sharing learning, including film and visual outputs, helped bring a complex subject to life, including the release of a short film featuring poetry by local artist Binta Yade, shaped from real interviews with Lambeth residents involved in youth violence reduction. These formats supported engagement beyond traditional reports and helped sustain interest in learning and improvement. 

While the evaluation did not seek to attribute long-term changes in serious youth violence outcomes at this stage, it has been effective in strengthening delivery, learning and decision-making within a complex system. Findings are now being taken forward through an Evaluation Implementation initiative, supporting refinement of theories of change, outcome measurement and more joined-up working across partners. The learning from this work will continue to shape Lambeth Made Safer and wider council priorities over the remaining life of the strategy.

• Build evaluation into delivery, not just reporting
• Utilise an Health Determinants Research Collaboration or other local authority-based research resource to anchor and support a major research/evaluation exercise such as this
• Secure senior buy-in early and revisit it often
• Use evaluation to support decision-making in constrained environments
• Centre community voice through public health and anti-racist principles
• Value qualitative insight alongside metrics
• Communicate learning creatively to widen impact.

Clare Bowerman: [email protected]

PHIRST South Bank evaluation page