Public diplomacy studies have been playing “catch-up” with public diplomacy practice. While we can trace the practice with the proper public diplomacy label to 1965 and to even further back to the late 1800s without the label, academic works have been limited until the last two decades. Up until 2001, fewer than 10 articles on public diplomacy were published annually. Currently, we have at least two peer-reviewed journals dedicated to public diplomacy studies, Public Diplomacy and Place Branding and Journal of Public Diplomacy,Footnote 1 alongside numerous research centers and graduate programs.

However, as scholars, we still have the “identity” question in our minds. Is public diplomacy a viable academic field or is it a part of other larger fields such as international relations or public relations? Has public diplomacy finally “emerged” as an academic field? When Gregory (2008), a practitioner-turned academic, eloquently pointed out the “sunrise of an academic field” for public diplomacy, he asked this very question moving: can we create a multidisciplinary field while maintaining academic standards?

While a longer discussion on the challenges faced on the way would be redundant for the readers of this journal, we would like to present a condensed reminder since we position our special issue as an attempt to overcome one of these challenges. One of the earlier challenges was our reliance on the American experience, to the extent that most studies were focusing solely on American public diplomacy as single case studies (Melissen 2005). We can, with confidence, argue that such an exclusive focus is no longer an obstacle as we have seen single case as well as comparative case studies on a growing list of countries in recent years, many of which we read in the pages of this journal.

Another important challenge was the lack of conceptual and theoretical frameworks. Gregory (2016), himself, later attempted to map the boundaries of this new academic field to avoid confounding of all international interactions as public diplomacy (see also Ayhan 2019). Others also continued this conceptual mapping of the field with taxonomies (Cull 2008; Fitzpatrick 2010; Pamment 2014), conceptual frameworks (Leonard et al. 2002; Zaharna 2009, 2013), normative frameworks (Cull 2019; Fitzpatrick 2007; Zaharna 2022), and structural literature review (Sevin et al. 2019). All these attempts were building blocks for a public diplomacy theory (Gilboa 2008). As an interdisciplinary endeavor, this search brought theories and concepts from international relations (Darnton 2020), public relations (Fitzpatrick et al. 2013; Golan et al. 2015; L'Etang 2009; Signitzer and Coombs 1992), media studies (Entman 2008; Golan 2013), and marketing (Anholt 2006; Gudjonsson 2005) among others.

Thanks to these efforts, public diplomacy literature is more or less saturated in terms of definitions, concepts, and frameworks. Indeed, in its relatively short lifespan, public diplomacy indeed moved from being a fringe topic to a growing field of study with its own theoretical discussions.

What led to this special issue has been a shared assumption of the guest editors: the next obstacle to overcome in our field is the need for more consolidation in terms of methodological approaches. Methodology obstacles have been less frequently addressed—and even when addressed, attempts were limited to empirical work based on anecdotes or limited quantitative data. The questions of how we study public diplomacy scientifically or critically, and how we evaluate the goals and outcomes of public diplomacy initiatives can help our field to produce more rigorous works.

When we launched our call for papers, we stated our objective as showcasing methodological discussions. We received over two dozen proposals. We, unfortunately, were not able to provide a platform for all the authors. After a 2-year journey, we are pleased to share a volume with eight original manuscripts covering qualitative, quantitative, and mixed-method research for public diplomacy.

We asked special issue authors what, in their views, would it mean for public diplomacy research to be more rigorous. Furthermore, we asked authors to focus on the methodological discussions, and use case studies only as illustrative examples without the empirical depth. We have a very diverse set of articles in this special issue: historical analysis, robust qualitative analysis, importing mainstream research methods including mixed methods, and impact evaluation.

First two articles in this special issue suggest methods for public diplomacy case studies with their historical context. Zhao Alexandre Huang, in his article, presents how historical and discursive institutionalism helps researchers better identify policy frames in public diplomacy. Huang uses the case of China’s institutionalization of its public diplomacy policy to illustrate how scholars can look at institutional changes to better understand how governments implement, mediate, rationalize, and legitimize their foreign policy through public diplomacy.

Seçkin Barış Gülmez and Miray Ateş’s article showcases how to adapt qualitative longitudinal research to trace continuity and change in a country’s public engagement policies over extended periods. In their illustrative case, Gülmez and Ateş examine how Germany portrayed itself and projected its image during three mega-events: The Berlin 1936 Olympics, the Munich 1972 Olympics, and the 2006 World Football Cup. They conclude that qualitative longitudinal research enables researchers to study the changes and continuity in a country’s public diplomacy strategies in the long term.

The following two articles help advance public diplomacy research by defining key concepts in public diplomacy and providing robust frameworks to capture them objectively. Phillip Arcenenaux and Lindsey M. Bier tackle one of the toughest concepts: culture. Given the fact that public diplomacy projects take place in intercultural contexts, their impacts need to be studied by taking such cultural differences into consideration. They advocate for mixed methods as they provide rigorous qualitative methods to help improve the reliability and validity of quantitative operationalization of public diplomacy concepts by contextualizing the communication process.

Steven L. Pike’s article explains how Q methodology can be applied to public diplomacy studies to analyze subjective perceptions. Pike points out the potential subjectivity bias in standardized public diplomacy evaluations and shows how Q methodology can make up for this bias. Pike suggests that using Q methodology enables researchers to observe aggregate patterns that arise from these observations while cautioning against over-interpreting the results by generalizing them outside of the sample.

The next three articles bring in some of the more mainstream social science methods to public diplomacy research. In their work, Imran Hasnat and Glenn Leshner present an overview of experimental methods. Although widely popular across different disciplines, public diplomacy scholarship has relatively limited experience with these methods. Hasnat and Leshner’s article presents a research agenda for using controlled experiments in public diplomacy research.

Hendrik W. Ohnesorge brings in yet another underutilized method in public diplomacy: comparative historical analysis (CHA). In his article, he suggests that CHA can advance empirical research in the public diplomacy field by contributing to more robust comparative frameworks.

Damien Spry and Kerrilee Lockyer take us through a mixed-method approach to digital diplomacy. In their article, they propose a triangulation approach that combines large data, small stories, and policy analysis to evaluate digital diplomacy projects. Through an illustrative case study of Australia, they bring together these three approaches by distant reading to map the ‘forest,’ close reading to examine the ‘trees,’ and analyzing the overarching documented public diplomacy strategies.

The final article in our special issue deals with the question of how to evaluate public diplomacy impact from the practitioners’ perspective. Yelena Osipova-Stocker, Eulynn Shiu, Thomas Layou, and Shawn Powers of the U.S. Agency for Global Media (USAGM) show us the complexities of public diplomacy research in the field. USAGM is active in over 100 countries, broadcasting in 62 languages. This diverse landscape of practice brings its own challenge of creating inclusive success indicators, data gathering techniques, and reporting methods. The article presents the case study of Voice of America in the Democratic Republic of Congo to illustrate the research–strategy–evaluation approach of USAGM’s impact model in practice.

We hope this special issue will function as a research method companion to all students, scholars, and practitioners of public diplomacy. In each article, readers will find in-depth discussions of specific research methods and types of questions these methods can help answer in public diplomacy. This special issue is by no means an exclusive method guide for public diplomacy. Indeed, it does not come close to covering the wide range of potential rigorous methodologies in the field. Most notably, we do not have any articles that talk about how to employ critical methods in public diplomacy (e.g., Kaneva 2011; Lee 2018). However, we hope that this is a first step in methodological discussions on public diplomacy, a discussion that should go on.

We would like to thank all the authors for their contributions and to apologize to many scholars whose works we could not accommodate. We also thank the reviewers, editors, and the staff of the journal for helping us get through this journey. While we acknowledge our field will face more obstacles, we hope this special issue will be a continuation of efforts working towards establishing public diplomacy as a robust and productive field of inquiry.