Member state delegations attending IPCC and IPBES plenaries often rely on dedicated technical expert support for the negotiations of the Summary for Policymakers (SPMs), during which the SPM is debated line-by-line, and the assessment approval is decided. These sessions are intense, highly structured, and politically sensitive—requiring not only a solid grasp of the underlying science, but also an understanding of negotiation dynamics, policy contexts and diplomacy.
In this post, we draw on our respective experiences supporting EU delegations at IPBES plenaries as part of the work conducted in the context of the Horizon-funded RESPIN project. The EU has the status of an enhanced observer at IPBES plenaries and takes part in the negotiations with delegates appointed by the European Commission. Our experiences refer specifically to the SPM negotiations for the Nexus Assessment1 and the Transformative Change Assessment2 approved during IPBES 11 in Windhoek, Namibia, in 2024, and for the Business and Biodiversity Assessment3 approved during IPBES 12 in Manchester, UK, in 2026.
As researchers, supporting the EU delegation was for us an opportunity to see more closely what happens when science enters multilateral decision-making spaces. One of the most striking aspects was how much preparation, coordination, and discipline this role requires before the plenary begins. It also made visible how scientific findings are carefully discussed, clarified, and negotiated into language that can be supported by all member states. This gave us a much deeper appreciation of both the importance and the difficulty of consensus-building in science-policy processes.
Based on these experiences, we share three practical insights that may be useful for those preparing to support delegations in future IPCC and IPBES plenaries:
1. Every delegation support experience is unique
There is no single formula for effective delegation support. Each experience is shaped by:
- The composition, working approach, and specific needs of the negotiating delegation, which is usually assembled on an ad hoc basis for each assessment.
- The characteristics of the assessment itself, including the scientific, political, and societal sensitivities surrounding the topic.
- The role of technical support can vary widely, from providing rapid, targeted scientific clarifications or technical work (track changes in wording, provide punctual references) to offering more strategic input during negotiations (flag inconsistencies across sections, identify the broader implications of a proposed edit, suggest intervention points and rationale). This can shift quickly depending on the plenary, as well as over the course of the same plenary.
2. IPCC and IPBES plenaries include multiple agenda points and are fast-paced
Plenaries bring together government representatives from member countries, assessment authors, and the secretariat. While the line‑by‑line approval of the SPM is often the most visible and time‑consuming element, plenaries also cover a broader range of agenda items, such as decisions on budgets, governance, and future work programmes. Because of this breadth, plenaries are typically organised into several working groups, often running in parallel. To manage this complexity, negotiating delegations usually designate specific delegates and support staff to follow individual working groups. These groups—including those involved in SPM negotiations—typically begin coordinating weeks or even months ahead of the plenary to review drafts and agree on a shared negotiation strategy. In the case of the European Union, the EU delegation also coordinates closely with EU Member States and their delegates. From a delegation support perspective, a few practical considerations can help:
- Preparation and anticipation: early coordination and preparation between the negotiating delegation and the technical support is essential to review SPM text and anticipate potential negotiation issues. Scientific support staff need to become very familiar with the assessment and SPM, and anticipate where scientific clarification may be most needed, and which lines may become contentious. The Earth Negotiations Bulletin offers concise summaries of negotiations, key positions, and contentious issues, although there is no record of which delegation proposed each amendment.
- Demanding pace and intensity: negotiations shift between rapid, high‑pressure discussions requiring immediate technical input and slower periods of prolonged wordsmithing discussions, often stretching late into the night.
- Quick and proactive thinking: in addition to suggest intervention points, technical support must rapidly judge whether a proposed edit is merely stylistic, politically strategic, or scientifically consequential, understanding the overall implications of the text evolution.
- Human dynamics: negotiations are conducted by people, and as such they are influenced by personalities, trust, fatigue, and informal interactions.
- Team effort: having more than one support person allows for taking turns, sharing cognitive load, and maintaining focus over long sessions.
- Preparing well both technically and mentally can make a substantial difference to effectively support negotiations at the Plenary. While not essential, it is of course helpful to have followed an assessment from the start as a reviewer, and to have some familiarity with plenary processes, for example through prior observer participation.
3. SPM approval, albeit grounded in science, is a political negotiation
Political negotiations do not necessarily focus on the validity of scientific findings, but on how these are framed, how strongly they are worded, what is emphasised, and what kind of policy implications are highlighted or shadowed. Effective support therefore goes beyond explaining what the science says. In advance of the plenary, it can be valuable to:
- understand and anticipate the interests, values, and geopolitical concerns that shape negotiating positions of other countries or negotiating blocs.
- identify where compromises are more likely to be sought or strongly resisted, and which kinds of compromises could be supported without undermining the science.
- Focusing exclusively on national (or EU) preferences and policy priorities can create blind spots. Insight into how other countries or groups may interpret, challenge, or reframe scientific findings can help any delegation navigate negotiations in a more strategic and constructive way.
A final takeaway
Strong delegation support sits at the intersection of understanding science, politics, and human dynamics. This requires a combination of technical expertise, situational awareness, and the ability to respond flexibly under pressure. In turn, supporting these multilateral processes offers a valuable window into how consensus is built in practice, and into the preparation, rigor, and patience such work demands.
1 IPBES (2024). Thematic Assessment Report on the Interlinkages among Biodiversity, Water, Food and Health of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Harrison, P. A., McElwee, P. D., and van Huysen, T. L. (eds.). IPBES secretariat, Bonn, Germany. DOI: https://doi.org/10.5281/zenodo.13850054
2 IPBES (2024). Thematic Assessment Report on the Underlying Causes of Biodiversity Loss and the Determinants of Transformative Change and Options for Achieving the 2050 Vision for Biodiversity of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. O’Brien, K., Garibaldi, L., and Agrawal, A. (eds.). IPBES secretariat, Bonn, Germany. DOI: https://doi.org/10.5281/zenodo.11382215
3 IPBES (2026). Methodological assessment of the impact and dependence of business on biodiversity and nature’s contributions to people of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Rueda X., Jones M., Polasky S., (eds.). IPBES secretariat, Bonn, Germany. DOI: https://doi.org/10.5281/zenodo.17185116
