The concept of Servant Leadership was introduced by Robert Greenleaf in the 1970s, and although in his works there is a very clear picture of servant leadership in philosophical terms, there is not an empirically validated definition of servant leadership. For this reason, numerous scholars worked individually on developing competing frameworks to define servant leadership since the mid-1990s; the result is that, throughout the scientific literature, the construct of servant leadership is defined by an inconsistent set of dimensions and there is still no consensus about an operational definition of the construct. In a similar way, since the end of the 1990s, numerous scholars developed different scales to measure servant leadership, based on different operational definitions. Accordingly, there is not an agreed upon measure of Servant Leadership; a few measures were used in a limited number of studies, and a relatively large number of measures were used in less than two. The chapter presents the most significant and used operational definitions, a detailed description of the development of the different measuring instruments, as well as a reference to some of the studies that used them, and a final section where the advantages and disadvantages of using certain measures are presented.
TopBackground
The concept of Servant Leadership was introduced by Robert Greenleaf in the 1970s, and although the depiction of what SL is in philosophical and practical terms is clear, there isn’t yet an agreed upon, empirically validated definition of SL (Laub, 1999; Van Dierendonck, 2011). Probably, the closest to a definition is Greenleaf’s famous quote:
The Servant-Leader is servant first…It begins with the natural feeling that one wants to serve, to serve first. Then conscious choice brings one to aspire to lead…The best test, and difficult to administer is this: Do those served grow as persons? Do they, while being served, become healthier, wiser, freer, more autonomous, and more likely themselves to become servants? And, what is the effect on the least privileged in society? Will they benefit, or at least not further be harmed? (Greenleaf, 1977, p. 7)
This is probably one of the most well-known paragraphs within the servant leadership community (Van Dierendonck, 2011), and also the starting point for any scholar working on an operationalization of the construct of Servant Leadership. However, since the inception of the concept in the 1970s research on SL was mostly anecdotal and non-empirical (Page & Wong, 2000; Whittington et al., 2006) and it took almost two decades for scholars to start working on an operational definition.
When compared to other leadership theories and models, the lack of an operational definition of SL made it difficult for scholars to develop research studies, and the literature of servant leadership lagged behind that of other leadership theories. For example, the concepts of Transformational Leadership or Leader-Member Exchange (LMX) Theory also date from the 1970s, but as scholars agreed early on basic definitions and measuring instruments for these theories, the state of the research is today far more advanced than in SL. In a recent article, the authors stated that their literature review “yielded more meta-analyses of Transformational Leadership than original empirical studies of Servant Leadership” (Barbuto & Wheeler, 2006, p. 303).