Great leaders do everything: a moderated mediation model of transformational leadership, trust in leader, helping behaviour, and idiosyncratic deals

On the basis of theories of transformational leadership and conservation of resources, this study investigates the impact of transformational leadership on helping behaviour indirectly via trust in leader. It also explores the moderating effect of idiosyncratic deals (i-deals) on the indirect relationship between transformational leadership and helping behaviour via trust in leader. We conducted a time-lagged two-wave survey among employees of seven companies in Jiangsu province, mainland China, and their immediate supervisors. The results show that transformational leadership has a negative indirect effect on helping behaviour via trust in leader. Moreover, i-deals strengthen the negative indirect effect of transformational leadership and helping behaviour via trust in leader. Our findings contribute to the literature on transformational leadership, trust in leader, and i-deals. In particular, our results provide insights into the dark side of those topics. Theoretical and practical implications are discussed.