Evaluating impact and generating causal evidence of results are becoming ever more important to enable effective development spending. Switzerland’s approach to impact evaluation applies multiple causal lenses and purpose-driven, context-sensitive methodological approaches. This enables the generation of robust, actionable evidence on effectiveness and impact across diverse interventions.
Fit for complexity: Switzerland’s approach to evaluating impact
Abstract
Development interventions often operate in fragile, complex contexts with multiple actors and non-linear pathways to change. With public spending under pressure – both domestically and internationally – there is growing demand for evidence on what works, how, and under which circumstances. Counterfactual evaluations offer causal evidence but are often too slow, narrow and resource-intensive. Although they work well for direct service delivery, such as in healthcare, they are less suitable when evaluating complex interventions. Switzerland’s impact evaluation approach uses fit for purpose methodologies, and integrates theory and practice, remaining feasible and relevant in complex contexts.
In line with OECD Development Assistance Committee’s Quality Standards for Development Evaluation and definitions, Switzerland has adopted a purpose-driven, context-sensitive approach to evaluating impact, embedding the following logic in its evaluation guidelines, internal quality assurance and commissioning practices:
Start with the main questions. Start by considering what decision-makers need to know for the evaluation to be credible and useful. Does the evaluation ask, “Did the intervention cause X, and by how much?” (attribution) or “Did the intervention plausibly contribute to X, how and under what conditions?” (contribution). While “attribution” assesses the direct causal links and isolates the intervention from other contextual factors, “contribution” includes them in the causal analysis to explore the interplay between these factors and the intervention.
Apply contribution-attribution logic explicitly. Attribution approaches can be applied when direct causal effects are of interest and valid counterfactuals can be constructed. In contexts where multiple interacting factors shape outcomes and impacts, such as interventions contributing to higher-level policy or systems change, or which have results that are difficult to quantify, analysing contribution of specific interventions is useful.
Use appropriate methodological approaches. Evaluations assess causal relationships using theory-based approaches, including contribution analysis, realist evaluation, qualitative comparative analysis, and quasi-experimental and experimental designs such as regression discontinuity, difference-in-difference and randomised controlled trials.
To guide staff and partners planning on conducting an evaluation, the table below outlines the questions, intervention requirements, approaches and methods that can be used when applying either a contribution or attribution lens to evaluating impact. The three guiding questions reflect different knowledge interests regarding the causal relationship between an intervention and an observed change.
Note: For further information on the different evaluation approaches and methods, see Better Evaluation.
Source: Based on SECO (2025), Evaluation Guidelines, https://www.seco-cooperation.admin.ch/dam/fr/sd-web/32OekmBTrhsI/Evaluations%20Guidelines%20SECO%20WE.pdf.
Applying a complexity-aware and user-focused approaches to evaluating impact has led to clearer causal claims, better learning and more decision-relevant evidence. The following examples show how selecting the right causal lens allows for meeting specific knowledge interests, and selection of robust methodological approaches that have credibility across different intervention realities.
A contribution-focused impact evaluation for the Swiss-funded Global Reporting Initiative (GRI) examined causal links between GRI interventions and observed changes using a contribution analysis, a theory-based evaluation approach, an outcome harvesting method, and semi-structured interviews and qualitative content analysis. It found that GRI made a credible and meaningful contribution to changes in sustainability reporting systems, but that these changes emerged from interacting causal factors rather than from GRI interventions alone. In a complex, multi-actor context, isolating GRI as the sole cause of change was neither feasible nor meaningful. The evaluation therefore assessed GRI’s contribution alongside other influencing factors, such as market pressures and regulatory dynamics. This approach generated evidence of how reporting standards contributed to companies’ sustainability practices and informed the formulation of targeted recommendations for the next funding phase.
An attribution-oriented impact evaluation for the Swiss-funded “Empleando Futuro” Social Impact Bond in Colombia applied a counterfactual approach using a difference-in-difference design based on employment data. The evaluation demonstrated that the training and job placement intervention led to significant improvements in labour market outcomes. Participants were 12 percentage points more likely to access formal employment three months after intervention completion, around 16 percentage points more likely after six months, and about 8 percentage points more likely after fifteen months, compared to the control group. This provided clear evidence of causal attribution, supporting results-based financing decisions and the scaling of the intervention.
Choosing the right methodology – and expertise to implement it – are essential for quality impact evaluation. While contribution may be analysed at different stages (i.e. mid-, final-term, or ex post), attribution requires early involvement and evaluation design choices (e.g. selecting a control or comparison group, establishing a pipeline approach and collecting baseline data). For both, evaluators need to work with implementers to articulate and refine theories of change and formulate hypotheses to be investigated. This requires in-depth methodological and subject-matter expertise.
Evaluating a broader scope enhances learning and enables adaptive implementation. A contribution-focused approach assesses impact where attribution is not suitable, as it enables the analysis of higher-level effects, system change, or outcomes that are difficult to quantify. This approach strengthens accountability and supports cause and effect learning. Causal evidence supports better decision making, allowing adjustments to interventions during implementation, or replicating and scaling of interventions after closure.
Investing in evaluation design strengthens usefulness. Ensuring evaluation questions reflect the intended knowledge needs leads to more useful and relevant evaluations. Clarifying what needs to be learnt can require considerable effort. Investing in a strong evaluation design phase may be more time-intensive upfront, but it ultimately leads to more useful results. Outlining methodological approach options in the terms of reference helps clarify required expertise, align expectations and ensure the evaluation budget matches the resource requirements of the chosen approach.
SECO-WE (2025), Evaluation Guidelines, https://www.seco-cooperation.admin.ch/dam/fr/sd-web/32OekmBTrhsI/Evaluations%20Guidelines%20SECO%20WE.pdf.
SECO-WE (2025), Performance and Quality Report of the Evaluated Portfolio of SECO’s Development Cooperation 2023–2024, https://www.seco-cooperation.admin.ch/en/accountability-and-effectiveness-reports.
Giordano, N. & I. Mundzir (2024), Impact Evaluation for Global Reporting Initiative (GRI), https://www.aramis.admin.ch/Texte/?ProjectID=57688.
Chaparro J.C., G.A. García & M. Cardona (2020), Impact Evaluation of "Employing Futuro" - First Social Impact Bond in Latin America, https://www.aramis.admin.ch/Texte/?ProjectID=57693.
Quadrant Conseil (2017), Impact Evaluation Approach Tree, https://www.quadrant-conseil.fr/ressources/impacttree.html.
Stern, E. (2015), Impact Evaluation: A Guide for Commissioners and Managers, https://www.bond.org.uk/wp-content/uploads/2022/09/impact_evaluation_guide_0515-2.pdf.
Stern, E. et al. (2012), Broadening the Range of Designs and Methods for Impact Evaluations, https://assets.publishing.service.gov.uk/media/5a74eba7e5274a59fa71600d/design-method-impact-eval.pdf.
IEG, “Evaluation Methods Resources”, Independent Evaluation Group - World Bank Group, https://ieg.worldbankgroup.org/methods-resources.
OECD (2023), Glossary of Key Terms in Evaluation and Results-Based Management for Sustainable Development (Second Edition), OECD Publishing, Paris, https://doi.org/10.1787/632da462-en-fr-es.
OECD (2023), “Evaluating development co‑operation”, Development Co-operation Tools Insights Practices, https://www.oecd.org/en/publications/development-co-operation-tips-tools-insights-practices_be69e0cf-en/evaluating-development-co-operation_5602e1f7-en.html.
OECD (2021), Applying Evaluation Criteria Thoughtfully, OECD Publishing, Paris, https://doi.org/10.1787/543e84ed-en.
OECD (2010), Quality Standards for Development Evaluation, DAC Guidelines and Reference Series, OECD Publishing, Paris, https://doi.org/10.1787/9789264083905-en.
OECD (1991), Principles for Evaluation of Development Assistance, Development Assistance Committee, OCDE/GD(91)208, https://one.oecd.org/document/OCDE/GD(91)208/en/pdf.
To learn more about Switzerland’s development co-operation, see:
OECD, Switzerland, Development Co-operation Profiles, OECD Publishing, Paris.
More In Practice examples are available on Development Co-operation TIPs • Tools Insights Practices.
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