Potential Impacts
Nudging interventions can generate change across three interconnected levels of social transformation (all of which were examined in PLANET4B).
- Intrapersonal impacts involve shifts in knowledge, attitudes, perceptions, and behaviours of individuals. These can be measured through surveys, interviews, or self-reflection tools that capture how participants’ awareness and decision-making are affected by exposure to a nudge.
- Interpersonal impacts emerge when changes in one person’s behaviour influence others, producing spillover effects. These can be studied by observing patterns of interaction, conversations, or behavioural diffusion among people who were not originally part of the experiment.
- Institutional impacts concern the development of new default rules, practices, narratives, or discourses. These may be traced by examining how organisations, businesses, or broader governance structures adopt new norms and practices, and how biodiversity-related considerations enter institutional agendas.
In this video Ilkhom Soliev explains the multiple impacts of the Supermarket Nudging Method:
From a methodological perspective, experimental designs allow impacts to be assessed by comparing changes between a control group and a treatment group. The analytical task is to establish the extent to which observed changes in behaviour can be attributed to the intervention itself. For example, in a supermarket field experiment, the question is whether differences in purchasing behaviour can be causally linked to the nudges embedded in shopping trolleys.
Longer-term impacts can be investigated through follow-up research that examines whether interventions triggered further actions or institutional change. These might include supermarkets reorganising product placement, hiring staff to focus on sustainability initiatives, adopting new internal policies, or introducing capacity-building measures. Methodologically, for example, this can take the form of:
- In-depth case studies of the sites where experiments took place
- Cross-sectional studies to identify associations across a larger number of participants
- Longitudinal research to track decision-making and behavioural change over time
- Comparative studies that explore how similar interventions work across different cultural or organisational contexts
In these ways, nudging experiments can move beyond immediate behavioural shifts to contribute to wider processes of organisational learning, governance innovation, and systemic change.
In this video Ilkhom Soliev explains the impacts of the nudging method within the PLANET4B case study:
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Adaptions
Nudging interventions can be adapted to a wide range of settings beyond supermarkets. The principles remain the same: to change how choices are presented in ways that make pro-biodiversity behaviour more visible, attractive, or convenient, while keeping all options open.
In this video Ilkhom Soliev explains how the Supermarket Nudging Method could be adapted:
Adapting the method
Nudging can take many forms, depending on the target audience and the behaviour to be influenced. When planning future adaptations, consider the following examples:
- Prompting Biodiversity Awareness
Posters, prompts, or visual cues can be used in public spaces such as parks, community centres, or markets to encourage biodiversity-supportive behaviour, for instance by drawing attention to pollinator-friendly planting or responsible waste disposal. Highlighting pollinator-friendly areas acts as a nudge because it changes how people notice and relate to their surroundings. Signage or visual markers could encourage people to observe insects, take photographs, or explain how to replicate similar planting at home. By making biodiversity care visible and valued in public space, the intervention normalises pro-environmental behaviour and encourages subtle behavioural shifts such as avoiding trampling, littering, or removing plants. - Encouraging Biodiversity Conversations
Nudges can also work through social interaction rather than physical design. Encouraging conversations about biodiversity can be achieved through small prompts or questions placed in shared spaces, on digital platforms, or during community events. For example, a card on a noticeboard might ask, Which plants or birds have you noticed near your home this week?, or a supermarket receipt could include a biodiversity fact and a link to a local citizen science project. These small cues invite reflection and discussion, connecting individual awareness to collective understanding. The nudge works by activating curiosity and social norms, suggesting that caring for biodiversity is a shared and ordinary topic of conversation. When dialogue becomes routine, it helps to integrate biodiversity into social life and everyday decision-making. - Designing Sustainable Defaults
Opt-out nudges change the default so that the environmentally positive action occurs automatically, while people remain free to make another choice. This approach draws on a well-documented behavioural tendency: most individuals stick with pre-set options because they are easy, familiar, and appear to carry social approval. This can be applied in many settings. Office printers can default to double-sided printing; canteens can make plant-based dishes the first or default option; event organisers can provide re-usable cups unless participants request disposable ones. In each case, the design of the default aligns convenience with ecological care. For a default to remain ethical and effective, opting out must be straightforward and transparent. People should be able to make an alternative choice without penalty or confusion.
Each adaptation requires reflection on the underlying behaviour to be addressed, the values of the target group, and the level of intervention appropriate to the setting. The COM-B model (Capability, Opportunity, Motivation – Behaviour) can be a useful guide for identifying which factors to focus on. For instance, a nudge may build motivation through emotional or moral appeal, increase opportunity by repositioning products, or strengthen capability through simple information cues.
