Table 2.

Brief descriptions of three participatory methodologies and examples where they have been used to tackle complex problems.

Participatory methodology	Description	Examples of methodology in use
Deliberative forums	Deliberation is defined as the action of thinking carefully about something, especially in order to reach a decision (99). According to Gregory et al. (98), deliberative approaches to community engagement centre on involving the community in discussion and deliberation about issues, ideally leading to concrete proposals that can be adopted by policy makers. The process involves ordinary citizens being willing to tackle difficult, often value-laden problems. A key part of these types of forums is the recognition that participants will absorb educational background materials and engage in exchanges with others, who may have different perspectives, experiences, and reasons with one another and in doing so will develop their views and discover their interests (91). In contrast to the commonly-utilized focus group, Carcasson (90) emphasizes that deliberative engagement focuses on developing mutual understanding and genuine interaction across perspectives, which then provides a base to support the constant adjustment, negotiation, and creativity required to tackle wicked problems. These types of interactions do however require extensive community capacity and are indeed a cultural shift away from an over-reliance on either expert or adversarial processes.	The Irish Citizens' Assembly is an example of a deliberative forum [see Farrell et al. (100) for full description] where members of the assembly were regular citizens selected from the wider population and participated in facilitated roundtable discussions on a monthly basis. Presentations by advocacy groups and on occasions (notably when discussing abortion) personal testimonials by a number of women were also included. Together, the creation of two deliberative mini-publics in quick succession [The Irish Citizens' Assembly (2016–2018) and the early Convention on the Constitution (2012–2014)] played a significant role in supporting key referendums for constitutional change that followed [marriage equality in 2015 (101), and abortion in 2018 (102)].In a dairy-specific example, participatory policy making was recently employed in the United Kingdom to enable groups of dairy producers to deliberate and develop an antimicrobial stewardship policy [see (103) for full description]. The authors noted that “the participatory process provided comprehensive learning for all involved and allowed for the integration of science and the producers' own knowledge and experience. The process led to the development of credible and practical recommendations designed to deliver real on-farm changes” (103).
Reflexive Interactive Design (RIO)	According to Bos and Koerkamp (97), the RIO approach (a Dutch acronym for Reflexive Interactive Design) was first proposed to aid the discussions surrounding agricultural issues that are viewed to be complex and value-laden. The approach recognizes that livestock production's historical focus on volume and cost-efficiency has increasingly been confronted with a series of self-generated risks and unwanted side effects [see also (104) for discussion on risks to sustainability arising from current dairy management practices in the US]. The RIO framework places equal focus on both technical and social challenges and seeks to redesign agricultural systems in ways that can overcome these constraints to be truly sustainable (97). According to the same authors, determining the fundamental needs of all actors that are involved in a system (including farmers, the general public and consumers as well as the animals themselves) and formulating them into a “Brief of Requirements” is a key starting point of this approach. Their aim is to then redesign systems that simultaneously speak to the needs of all the different actors, instead of weighing the pros and cons of the various interests against each other (97).	An example where RIO methodology was used is the Pork Opportunities project in the Netherlands (2008-2010) [see (105)]. Briefly, the aim was to redesign the pig husbandry system to “produce pork in a way that is good for People, Planet, Profit and Pigs.” This project began with a system analysis that identified and assessed the needs of the pig, pig farmers, the environment and the consumer/citizen. Key challenges in the current pig production system were then identified as were possibilities for change. Design goals were formulated, key functions were identified and solutions to these functions were generated to fulfill the needs of all actors. A selection of these solutions was then combined to render new designs of pig husbandry systems.The RIO approach was also used by Romera et al. (106) to re-design sustainable dairy systems in New Zealand. The authors argued that this approach offered an opportunity for more profound reflexion within the dairy industry and is tailored to wicked problems and situations with apparent value conflicts. It first set out to develop desirable “ideal” systems; participants were actively encouraged to not focus on technical or economic feasibility. Only after completion of this phase were the participants then encouraged to focus on the feasibility of the concepts. Animals were considered as key actors alongside farmers as were the consumers and the New Zealand citizens; this latter aspect of the process was driven in large part by the recognition and acceptance by all involved that animals are sentient beings, whose lives could be profoundly affected by the designs if they were to be implemented.
Human Centred Design	Human Centred Design is rooted in fields such as ergonomics, computer science, and artificial intelligence (107). This approach also places priority on deeply respecting all views, recognizing that in order to develop creative, innovative solutions that are rooted in people's actual needs, the voices of all stakeholders must be included [see (108)]. The process involves three main phases: Inspiration, Ideation and Implementation, and is designed to help participants learn directly from each other, open themselves up to a breadth of creative possibilities, and then zero in on what is most desirable, feasible and viable for all actors involved [see (108)].	Human Centred Design has been used to address complex issues such as healthcare, and was utilized by The Best Babies Zone initiative, a multi-year project aimed at reducing inequities in infant mortality rates and enhancing overall population health in Oakland, California (109). As the authors describe, this approach was used to design solutions that addressed the deeply-rooted, complex social and economic conditions that are important drivers of health inequities in this region. A diverse team representing organizations from multiple sectors were invited to attend; stakeholders represented government, design, community, and economic development and individuals who worked in the neighbourhood. Collectively the goal was for all stakeholders to become familiar with the complexity of the situation in a context that deepened their understanding and empathy. Based on insights from working in the community, the team brainstormed over 100 concepts to address the design challenge and integrated community members' feedback at an early stage of the planning process.