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Evaluation & Learning Partner

Fiscal Measures for Healthier Food and Drink Project
Terms of Reference: External Evaluation & Learning Partner

About the project

The project started in March 2022 and will run until September 2024. It is a partnership between Sustain, the Food Foundation and the Obesity Health Alliance, working in collaboration with British Heart Foundation and our main funder, Impact on Urban Health. 

The Soft Drinks Industry Levy has succeeded in removing around 48,000 tonnes of sugar from soft drinks since it was introduced in 2018, reducing household consumption by 20%, or an equivalent of 30g per household per week. Overall, sales of soft drinks have not declined, instead the Levy has supported a transition to the production, marketing, sales and consumption of low and no-sugar drinks.  The independent National Food Strategy recommended the introduction of a sugar and salt reformulation tax into the whole of the food and drink industry, however whilst the Government has recognised the success of SDIL, it has not committed to any further form of industry duties on HFSS food and drink.

The project intends to achieve the introduction of broader food and drink industry levies, with the aim of incentivising healthy reformulation and disincentivising the manufacture, sale, marketing, purchase and consumption of HFSS food and drink. The project aims to:

  • Address evidence gaps to demonstrate the impact of a levy in supporting transition to healthier diets, to bolster the case to Government
  • Build political, parliamentary and stakeholder engagement in support of advocating further fiscal interventions
  • Create a platform of public and civil society support for expansion of models building on the success of SDIL, including calling for revenues to bolster investment in initiatives to increase access to healthier diets.

The project comprises three main areas of activity, each led by a different partner. 




Lead org

1. Policy & Research Evidence generation

Synthesise evidence on impact of fiscal measures, commission modelling to demonstrate how a levy can avoid being regressive, model impact of fiscal measures on health outcomes and healthcare savings

Food Foundation

2. Public affairs and political influencing

Influencing in Govt & Parliament – policy making & political traction

Obesity Health Alliance  

3. Campaign coalition building and communications

Lay foundations for public campaigning, including polling and focus groups to understand and evidence support for a tax when framed in the right way (avoiding use of the word tax, association messaging with improved health outcomes, revenue being ring-fenced for expenditure on health etc.), key messaging and comms strategy development, coalition assembly, and campaign delivery.


The approach to learning

There are two core questions that this work seeks to learn about, with multiple sub-questions:

  1. What progress are we making as a coalition, towards our end goal of achieving healthy reformulation via fiscal measures? The specific fiscal measures may - or may not be - achieved during the timeframe of this project. The evaluation framework we create will enable us to track progress against key metrics - what we deliver, and what traction or outcomes they generate. The aim is to generate evidence and insight to help inform our ongoing approach and strategy.  We will work with a Learning/Evaluation partner to establish the degree to which outcomes have been generated and how far we can attribute these to our interventions and activities.
    • Our evaluation framework will need to map the data we can already access, and where we need to invest e.g. public polling, MP engagement, media traction and analysis of content.
  2. What are we learning about how successful our approaches have been? Ongoing monitoring, review and data collection will provide insight into what is working about the approaches we are taking, what we are learning as a coalition working together, and include tracking of the external environment and wider factors at play that are positively or negatively affecting our ability to create traction. There are a number of approaches that we are exploring in this project, which each workstream lead will need to develop:
    • The generation of new evidence and analysis on the potential impact of any new fiscal measure on industry reformulation, shopping basket price shifts etc, and potential to trigger healthier shopping opportunities, especially for those on low incomes
    • The direct outreach and engagement with key political targets, allies, wider influencers and industry
    • The development of creative communications frames, toolkits and campaign tactics to mobilise support for the campaign.

Ensuring a process of review, learning and adaptation based on what is working, where we’re gaining traction, and where we need to change course or refocus efforts.


  • Sustain will lead the overall evaluation framework and relationship with an external learning & evaluation partner
  • All partners will be responsible for establishing and measuring the outputs (and where possible) outcomes most closely related to the activity they deliver, and learning associated with these
  • Sustain will lead on commissioning an external learning partner to facilitate the establishment of our overall evaluation framework, support the ongoing monitoring and review of progress, and our approach for the end of project evaluation.

Role of External Learning Partner

  • Take an overview of what we want to learn about in totality, and to build in timeframes and mechanisms for reflecting and acting on what we are learning, to inform the approach we take. This would involve finalising a learning framework (using the content in this document as a starting point).
  • Propose the approach to measuring long-term success, including:
    • What do we need to measure to understand whether we are achieving our outcomes over time? For example, parliamentary and media insight; change in language and framing of debate; media tracking and public polling; references to research/briefings in policy documentation and impact of written outputs.
    • What approach should we take to understanding what change we drive over the course of the project, and what contribution this project has made to the introduction of fiscal measures (if achieved) or support for fiscal measures (if a fiscal measure isn’t introduced within the timescale of the project)?
    • What learning related to coalition campaigning could be of use for any future work on this topic, or other similar coalition campaigning in the future?

The External Learning Partner will also work with Sustain (and other project partners) to identify and agree any further external technical or expert support for the evaluation and learning process, which may be additionally commissioned, once the evaluation framework is agreed.

Expressions of Interest

Please respond to this document outlining:

  • Your response to the initial draft Evaluation and Learning approach as outlined in this document
  • The methodology you would use for facilitating the development and finalisation of an evaluation framework
  • How you propose to support the process of interim review and learning during the life of the project from July/August 2022 to September 2024, and the approach you’d recommend for the final evaluation.
  • The background skills, experience of the consultant or team that would support the project.
  • A proposed budget for the work, including details of any daily rate and VAT applicable.

As a guide, we anticipate a contract of up to 20 days for facilitation of the initial evaluation framework and ongoing process facilitation.

An initial budget for establishing the evaluation framework and process facilitation of £8-10,000 is envisaged. Additional budget support for specific additional deliverables e.g. Data analysis or insight gathering will be assigned upon agreement of the evaluation plan.

Deadline for responses: 5pm on Monday 1 August 2022 to


If you wish to discuss this project, please contact Barbara Crowther, Children’s Food Campaign Co-ordinator, Sustain

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