This study is a comprehensive analysis of the development of the ‘engagement’ rhetoric in the pertinent academic literature on science communication and in science policy documents. By way of a content analysis of articles published in three leading science communication journals and a selection of science policy documents from the United Kingdom (UK), the United States of America (USA), the European Union (EU), and South Africa (SA), the variety of motives underlying this rhetoric, as well as the impact it has on science policies, are analyzed. The analysis of the science communication journals reveals an increasingly vague and inclusive definition of ‘engagement’ as well as of the ‘public’ being addressed, and a diverse range of motives driving the rhetoric. Similar observations can be made about the science policy documents. This study corroborates an earlier diagnosis that rhetoric is running ahead of practice and suggests that communication and engagement with clearly defined stakeholder groups about specific problems and the pertinent scientific knowledge will be a more successful manner of ‘engagement’. The ‘engagement discourse’ has assumed a prominent role in the science policy rhetoric in the European Union (EU), the United States of America (USA) and beyond, to medium-income countries such as South Africa (SA). Bensaude-Vincent diagnosed the engagement rhetoric as ‘buzz’, having its origin in management and marketing , p. 239.Concepts, metaphors or more generally rhetoric, serve a multitude of actors and their interests. They mediate between different institutions, may legitimate or de-legitimate positions of power, and signal societal change . The ‘scFirstly, the term ‘engagement’ is side-lining the conflict characterizing modern democracies, between political representatives, legitimated by popular vote, and experts legitimated by expertise based on scientific knowledge, or between democratic and technocratic rule. The conflict between these two sources of legitimacy has increased in intensity for two main reasons. On the one hand, problems of government have become more complex and thereby the need to rely on scientific knowledge represented by experts has grown, conferring more actual power on them. On the other hand, citizens’ rights and claims to political influence have expanded over the past two centuries .Secondly, ‘public engagement’ ignores the functional differentiation of social systems, especially between the roles of citizens and of professionals. Participation in political debates and decision-making in a democracy is open to every citizen, regardless of qualification. Science, conversely, is a highly specialized social system participation in which requires, in most cases, the completion of years of advanced higher education with some kind of certification as the entry ticket to a professional role. Participation, in the sense of engagement, normally does not intend the acquisition of professional expertise. Nevertheless, forms and degrees of participation in science by non-scientists vary considerably, e.g., depending on the accessibility of the disciplines concerned and the kind of contributions expected from citizens. These range from data collection in large spatial and temporal scales  to actual innovation through the exchange of information , 5 and uFinally, a further aspect of the ‘success’ of the rhetoric is its global spread, though with some variation, across the socio-economic and cultural differences and differences in political and science systems between nations. Neo-institutionalists have identified this phenomenon as isomorphism by imitation . In factIn this study, we trace the origins and evolution of the discourse on ‘public engagement with science’, both in the academic discourse and in the broader political context. We aim to identify the different motivations for engagement and how they are undergoing change in the transition of the concept from one context to the other. The ultimate question is whether it is likely to succeed in bridging the gap between the popular representative and the expert knowledge-based types of legitimacy, i.e. in mediating between representative democratic and technocratic forms of governance.Two recent studies are especially pertinent to our own. They focus on the emergence of the discourse on ‘public engagement’, the conceptual vagueness of the term itself, the motives behind it, i.e. the functions that are associated with it, and the obstacles that frustrate its implementation , 15. TheOne issue discussed with respect to participation and engagement is the different forms they may take. The dichotomous distinction between ‘invited’ and ‘uninvited’ participation or engagement is fundamental in this context . UninvitThe typology of governance suggested by Hagendijk and Irwin , p. 172 Rowe and Frewer , p. 254 The diverse forms of engagement respond to two threats of legitimacy: 1) the threatened legitimacy of science  and 2) the threatened legitimacy of governments. Both threats manifested in public protests against particular decisions about scientific and technological programs. These threats have increased in urgency since science has become a crucial factor in national economies, thus increasing their competition for innovation advantages. ‘Engagement’ is promoted with the expectation that involving the public in science will contribute to knowledge production and the improvement of the workforce, thereby augmenting innovative capacity . All theThe issue of legitimation as an underlying motive of the ‘engagement’ rhetoric raises the question of the kinds of publics it addresses. When, in the 1970s, student activists at universities set up ‘science shops’, the precursors of present citizen science projects, they addressed the local civil society and NGOs as their clientele . When thAs the rhetoric became more ambitious and shifted to ‘public engagement with science’, it also became less specific with respect to who this public is that is supposed to be engaged with or be engaged by science . The impumbrella term–that encompasses many kinds of activity including science festivals, centers, museums, cafes, media, consultations, feedback techniques, and public dialogue”  appearing on radio, giving a public lecture, designing activities for children, and so on” , p. 244.“[…] public or school conferences, appearances on radio, interviews in newspapers, written work for non-specialist audiences, participation in open days or science festivals, collaboration with associations, design of activities for children, and so on” , p. 54.“[…] lecturing in public or in schools, giving interviews to journalists for newspapers, radio or television, writing popular science books, writing the odd article for newspapers or magazines oneself, taking part in public debates, volunteering as an expert for a consensus conference or a ‘café scientifique,’ collaborating with non-governmental organizations (NGOs) and associations as advisors or activists, and more” , p. 3.“[…] it can take the form of one-way attempts to provide content through the news media, advertising, Internet sites, or presentations, to more interactive activities where participants are invited to participate in two-way dialogue” , p. 653.One source of the discourse on ‘engagement’ is ‘upstream technology assessment’, the idea that the public should be involved at an early stage in the development of new technologies. Rogers-Hayden and Pidgeon define ‘upstream engagement’ as:“Dialogue and deliberation amongst affected parties about a potentially controversial technological issue at an early stage of the research and development process and in advance of significant applications or social controversy” , p. 346.Similarly, Krabbenborg and Mulder describe upstream public engagement as follows:“[…] a new governance vision in which citizens and civil society organizations right from the early stages of research and development trajectories, engage in dialogue with technology developers, such as scientists and industrialists, about the (tacit) assumptions, meanings, values, and consequences of new science and technology for society” , p. 453.Notwithstanding its noble intentions, Rogers-Hayden and Pidgeon point out that “the notion of upstream engagement is a contested concept with a range of associated dilemmas and tensions” , p. 345.Answering RQ2, public engagement with science is motivated in various ways. Within the sample of academic articles analyzed for this study (N = 86), the majority (n = 72) mention a motivation or motivations for public engagement with science. The most pertinent motivations are democratization, education, legitimation, innovation and inspiration. Engaging to empower citizens.In coding, we did not differentiate between the two possible interpretations of democratization, i.e. to participate competently in society (democratization of society) and/or to participate in science (democratization of science). They occurred in different combinations. These are pertinent examples:“There is a strong democratic principle that citizens will be better able to contribute to decisions that are likely to have an impact on their lives and become engaged with the decision-making process” , p. 368.“A shift from public understanding to public engagement with science has been characterized as citizen-oriented science or a more open, egalitarian, and participatory science. These descriptions aim to acknowledge the importance of citizens’ concerns and perspectives and consider the dialog between scientific and citizen groups to be a crucial element of the modern ways of knowledge production and governance” , p. 1.“Diversity is an important principle of deliberative democracy on which public engagement activities should be based […] The scholarship on public engagement in the context of Western liberal democracies in recent times has acknowledged the need to ‘hear all voices’/include multiple perspectives. Yet, in the realm of science and technology, this goal still falls short of what is in fact needed–rethinking the very architecture of decision-making processes on science policy so that it truly embodies cultural diversity” , p. 288.Engaging to inform and educate the public about science, improving  public access to scientific knowledge.Assessments as to how much prior knowledge is needed for engagement, and if providing such knowledge should be an objective, vary.“Our findings suggest that little prior formal science knowledge is necessary in a debate of this kind […] Particularly for the active/generative participants, what was needed was a critical understanding of the nature of scientific evidence and a grasp of the way that wider issues influence debates about science and the value that is placed on the formal scientific evidence. In terms of the science curriculum, it follows that there is a need to teach for an understanding of scientific evidence and for pupils to actively engage with topical science-based issues” , p. 362.“The general public should be enabled to understand complex systems, uncertainty, statistics, and the difference between science and pseudoscience” , p. 290.“Once engagement was initiated, our work helped build citizens’ knowledge about nanotechnology, as well as their confidence and efficacy levels to understand and engage with it—which in turn built their capacities to engage further with other citizens, scientists, and policymakers”  making decisions without public support is liable to lead to a number of practical difficulties, such as confrontation, disruption, boycott, and public distrust. Indeed, a decline in trust in policymakers has been widely noted and is regarded as having compromised the perceived legitimacy of governance in some areas of policy development. A transition seems to have occurred from a position where information was seen as the key to resolving a knowledge deficit, and so resolving lay opposition, to one in which regaining trust in governments and regulators is seen as vital to solving a perceived legitimation (or trust) deficit” , p. 332.Engaging to promote innovation.One motivation for engagement is that it will increase innovation. We included in this the argument that the public, i.e. citizens, are a valuable source of knowledge  and should be called upon to contribute to knowledge production. Here the emphasis is often on bridge building and including knowledge outside ‘formal’ science.“Local community engagement and support is seen as key to the continued development and the increasing deployment [of renewable energy technologies]” , p. 37.“Lay citizens have valuable knowledge and perspectives to bring to discussions about technological developments, and their input can contribute to more comprehensive and robust societal decisions about these developments”  The data show that children as young as 10 are thoughtful about their futures, and may already be forming strong opinions. Indeed one might say that science engagement initiatives that support and target primary age students would not be wasting their time” [“Another purpose of public engagement initiatives is to reverse the decline of science as both an academic subject and a profession […] This leads many public engagement initiatives to focus on directly improving the attitudes of young people toward science as an academic subject rather than improving attitudes toward science in general”  it’s a kind of deficit model again, a deficit model of public engagement—we’ll dialogue in order so that they understand us better and will agree with us, instead of we’ll sit them down and educate them” , p. 355.Ellis, Waterton and Wynne explain how the danger in this lies in the possibility of silencing the voices of the very publics with whom engagement is sought:“If public engagement exercises remain stuck in a deficit style of science communication, this will ‘ironically’ help to ‘reinstate the authority of science by subtle means involving erasure of the very publics being invited to participate’” , p. 504.“Are engagement efforts really intended to involve citizens in ways that could give them a meaningful voice in science and technology decision-making? Or is the goal to increase citizens’ trust in scientists and policymakers or to encourage them to accept nanotechnology products? Relatively few engagement projects, for example, include processes intended to link citizens’ recommendations, concerns, and questions to actual policy processes or decision-makers”  it is a culture of public engagement that still seems to be lacking among most research institutions in Europe–meaning an organizational culture in which PE is appropriately recognized, evaluated and rewarded as part and parcel of the organization life, routine activities, and identity as well as a relevant element of the broader institutional landscape in which the organization operates” , p. 77.Other deterring factors include the fact that public engagement activities are viewed as being “at odds with traditional academic career paths and reward systems” , p. 178,Our sample of policy documents is too small to allow the construction of a timeline of the development of the ‘engagement’ rhetoric in the policy arena. It is indicative, however, that neither the Bodmer Report of 1985, nor the Wolfendale Report of 1995 mention the term ‘engagement’ at all. An indirectly related analysis by Conceição et al. for the occurrence of the term ‘public’ in EU framework programs shows a cycle beginning in FP 5 (1998–2002), morphing to ‘society at large’ and being replaced by ‘all stakeholders’ in H2020 (2014–2020) , p. 17.Some policymakers attempt to provide a catch-all definition by describing engagement as “an overarching term” that includes science, science communication, science literacy and science outreach and awareness , p. 13. Several definitions emphasize “mutual learning” and “dialogue” between experts and public audiences , 99. SimThe objective of ensuring public acceptance of new technologies, although expected to be very important to policymakers, is rarely explicitly mentioned in policy documents as a key objective for public engagement. EU policymakers suggest a tentative link between public engagement and public support by saying that it “offers the possibility of fostering new forms of public appraisal and maybe appreciation of research and technology development” , p. 4.It is specifically stated that the aim is “not about promoting blind faith in science or an unquestioning acceptance of its authority, but rather about providing everyone with the understanding and the opportunity to contribute to debates when science is discussed” , p. 28. with the public rather than at the public”  model of knowledge co-production where citizens and concerned groups get actively involved in the process of knowledge production is still far off” , p. 10, The fourth research question concerned the connection between the academic and the political discourses. Irwin commented on this relationship as early as 2006: “In remarkably few years, an (admittedly attenuated) form of the language of STS has been reconstructed as the language of policy. Without wishing to attribute uni-linear causality […] it is certainly possible to identify a resonance–and at times an explicitly-drawn connection–between previous STS research and the current policy emphasis on trust, transparency, uncertainty and dialogue” , p. 300.However, other sources prove–at least for the EU–that the academic (STS) community has, in fact, shaped the political engagement rhetoric as well as its successor: Responsible Research and Innovation (RRI), which signals a partial departure from the idealistic notions of public participation and a renewed emphasis on innovation. Macq, Tancoigne and Strasser explain: “In other terms, the effort of policymakers to embed public participation in scientific research more broadly remained confined to the science-society programs and did not spread beyond” , p. 506.The ‘engagement’ rhetoric is an expression of a fundamental problem that has haunted modern democratic societies for some time. As the decisions facing them have become ever more complex, governments have had to rely increasingly on the specialized advice of a scientific-technical elite of experts, resulting in a widening gap between governments and their electorates as well as an inescapable loss of legitimacy. This development has been met with attempts to re-capture citizens’ participation, be it with institutional innovations that engage ‘micro-publics’ in specialized decisions or with rhetoric calling for an unspecified engagement of the public at large. In the theoretical discussion, an attempt is made to straddle the contradiction between general democratic participation and elite expert knowledge through concepts like ‘democratization of expertise’.In investigating the development of the rhetoric over the last two decades, we observe a progressing generality and increasing ambition. It took almost a decade and a half for the rhetoric to reach its greatest impact in the political arena, with calls to ‘engage’, science communication programs and a host of events designed to bring science to the public. Likewise, it has taken considerable time for the academic community concerned to face the inescapable paradox of the ‘engagement’ project, i.e. that it remains a top-down enterprise. This demonstrates the enormous attraction of buzzwords or rhetoric that is distant from and above a reality that they intend to describe or even create. Nevertheless, it simultaneously confirms the immovable sociological observation of the functional differentiation of modern societies and the relative stability of institutions. Rather than succeeding in its intended purpose of re-establishing legitimacy for the institution of science and democratic governments by bridging the gap between them, it seems that the ‘engagement’ rhetoric has not only outpaced practice, but also become diluted in the process.In the current study, we analyzed only 19 policy documents, compared to a much larger set of academic articles. It should be noted that it is not possible to select policy documents with the same rigorous inclusion or exclusion criteria that can be applied to the selection of academic texts. However, the term “public engagement” spilled over into the policy arena following increased attention in the academic arena, and therefore started to appear in policy documents more recently, compared to its occurrence in academic articles. Earlier policies regarding the relationships between science and society mostly refer to concepts such as “science literacy” or “public understanding of science”. It would be highly meaningful to follow up this analysis with a study involving qualitative interviews with science policymakers in order to gain a richer understanding of their motivations, objectives and intentions with policy directives relevant to public engagement with science. However, that is unfortunately beyond the scope of the current study.S1 Appendix(DOCX)Click here for additional data file.S2 Appendix(DOCX)Click here for additional data file.S3 Appendix(DOCX)Click here for additional data file.