“…Unlike the prominent leadership theories and approaches, the main idea of LMX theory is based on how the quality of this theory leads to positive outcomes (Graen and Uhl-Bien, 1995). It is noted that although research on LMX theory has focused since the 2000s on investigating new ways of integrating this theory with other approaches, theories, constructs and processes, such as psychological contract (Caldwell and Hasan, 2016;Kasekende, 2017), transformational leadership theory and organizational commitment (Keskes et al, 2018), and social exchange (Pearse, 2017), it is still used as a predictor of work outcomes (Biswas, 2016;Choy et al, 2016;Erks et al, 2017;Sumner-Armstrong et al, 2008). This contradicts Erdogan and Bauer's (2014) claim that the evolution of LMX theory can be divided into four stages: In the 1970s stage, the Vertical Dyad Linkage Theory was introduced in the mid-1970s; in the 1980s stage, the focus was switched to LMX with the first empirical tests of the LMX construct; in the 1990s stage, LMX theory was used as predictor of positive outcomes; and from 2000 till now, LMX theory is being investigated through its integration with other theories and variables and as a mediator or a moderator.…”