Research into leadership has a long history. As an extensively explored theory, leadership has gained the attention of scholars worldwide, resulting in a wide variety of qualitative and quantitative approaches. Some scholars conceptualise leadership as a behaviour or personality, while others view it from a social information processing standpoint [1]. For many years, the importance of leadership was ignored in construction project management, as traditional researchers in this field mainly focused on the technology of the project [2,3].

The research paradigm of leadership in the construction industry began to change at the end of the 20th century. Across a broad research scope, early researchers conducted some interesting cross-sectional studies. For example, Sui Pheng and Lee [4] attempted to construct a managerial grid framework with an ancient Chinese strategy to develop the leadership of construction project management, while Weingardt [5] encouraged engineers to become more involved in leadership on all levels and to broaden their impacts on public policy. During this period, scholars realised that construction projects are people-oriented and that effective leadership is inevitably related to project success [6,7].

Since the beginning of the 21st century, leadership has been documented as an important skill of effective project leaders [8] and engineering management students [9] to accompany their technical skills. The behaviours of the project leader were found to be more significant in the prediction of project performance than the other team members’ characteristics [10]. Some quantitative and qualitative methods are gradually being introduced in the literature on leadership in construction projects. Liu et al. [11] developed a model to examine the power structures of the leaders of construction projects, while Fellows et al. [12] determined the leadership style and power relations. Odusami et al. [8] analysed the data from 60 project team leaders and concluded that project performance is significantly affected by the project manager’s leadership style. With a rapidly growing body of leadership research in construction projects, a number of studies have been conducted to determine the factors that contribute to an ideal construction project manager’s leadership style from a variety of perspectives [13,14,15,16,17]. Since the work of Turner and Müller [17], the study of the leadership of project managers has gained new momentum. Turner and Müller suggested that research should pay particular attention to the project manager’s competence and leadership style in relation to project success. For in-depth research, Müller and Turner [18] conducted qualitative and quantitative studies and concluded that the project manager’s leadership style influences project success and that different leadership styles are appropriate for different types of projects.

Over the past two decades, leadership has been regarded as a significant cause of project success or failure [19], and the personal and interpersonal factors of project managers that contribute to project performance have been investigated to some extent [20,21,22,23,24]. As shown in Figure 1, since the first literature appeared in 1992, the number of studies has increased every year. Against this background, several studies have reviewed and analysed the existing literature. Toor and Ofori [22] selected 49 studies and summarised the empirical research on leadership in the construction industry. Simmons et al. [23] conducted a critical review that predicted some future trends. In Graham’s [24] systematic review study, a computerised technique was used for bibliometric analysis to develop clear criteria to inform a thematic analysis and compare the analyses between multiple authors. Some other studies remain narrow in focus, dealing only with a certain branch of leadership theory in the construction industry [25,26,27]. Most studies, however, rely on the subjective judgment of experts, which leads to a lack of quantitative bibliometric analysis in this field. Although there are increasing numbers of publications in this field, little is known about the overall structure of the knowledge landscape.

Scientometrics is a branch of informatics that was defined by Nalimov and Mul’chenko [28] as “the quantitative methods of the research on the development of science as an informational process”. It can be considered as the quantitative analysis of patterns in the scientific literature to map knowledge structures and predict emerging trends in a research field. Compared with traditional bibliometrics, scientometrics provides in-depth quantitative analysis of the bibliographic information, such as countries, institutions, authors, keywords, and references [29]. The applications of the scientometrics software reduce the impact of a researcher’s subjective opinions on document records’ retrieval and screening. By using visualisation tools such as CiteSpace [30], VOSviewer [31] and Histcite [32], the knowledge structure of a scientific research field can be clearly presented. The scientometrics approach is the best way to explore research trends and key areas of study over time [33,34]. Therefore, various visualisation tools have been widely used in the field of technology management analysis [35]. By comparing the features of these software, we found that CiteSpace, which can visualise the networks of cooperation and the development of a research area over time, had the most features and was the most used.

2 Transactional leadership

3 Safety leadership

4 Team performance

5 Leadership interaction processes

6 Actual leader behaviour