How transformational leadership influences follower helping behavior: The role of trust and prosocial motivation YUE ZHU 1 AND SYED AKHTAR 2 * 1 Department of Human Resource Management, Zhejiang Gongshang University, Hangzhou, China 2 Department of Management, City University of Hong Kong, Kowloon, Hong Kong Summary We proposed and tested a moderated mediation model that jointly examines affect-based and cognition-based trust as the mediators and prosocial motivation as the moderator in relationships between transformational leadership and followers’ helping behavior towards coworkers. Data were collected from 348 sales and servicing employees and their supervisors in four private retail companies and five private manufacturing companies located in Southeast China. The results showed that both affect-based trust and cognition-based trust mediated the relationship between transformational leadership and followers’ helping behavior towards coworkers. Furthermore, moderated mediation analyses showed that affect-based trust mediated the relationship between transformational leadership and followers’ helping behavior towards coworkers only among employees with high prosocial motivation, whereas cognition-based trust mediated this relationship among only those with low prosocial motivation. Implications for the theory and practice of leadership are then discussed. Copyright © 2013 John Wiley & Sons, Ltd. Keywords: transformational leadership; cognition-based trust; affect-based trust; prosocial motivation; helping behavior In the past three decades, numerous theoretical and empirical studies have been devoted to examining transformational leadership effectiveness and its influencing processes (Barling, Christie, & Hoption, 2010). A cursory look at the predominant models of transformational leadership (e.g., Bass, 1985; Kark & Shamir, 2002) reveals that trust in the leader is often placed in a central role. Previous studies have mostly treated trust as a global construct and examined its central role as a mediator in the relationship between transformational leadership and followers’ work outcomes (e.g., MacKenzie, Podsakoff, & Rich, 2001; Podsakoff, MacKenzie, Moorman, & Fetter, 1990). On the basis of a meta-analytic review of trust in leaders, Dirks and Ferrin (2002) urged researchers to take into account multiple dimensions of trust, including affect-based and cognition-based trust and “attempt to distinguish between the processes involved” (p. 623), but only a limited number of them have actually heeded this call (Schaubroeck, Lam, & Peng, 2011; Yang & Mossholder, 2010; Yang, Mossholder, & Peng, 2009). We extend this limited stream of research by examining prosocial motivation as a moderator that may enhance or mitigate the mediated relationships between transformational leadership and work outcomes through affect-based and cognition-based trust. Because different dimensions of trust have been considered to fulfill distinct mediating functions (Schaubroeck et al., 2011), a model of leadership that incorporates trust should seek to identify boundary conditions under which dimensions of trust have differential effects on work outcomes (Dirks & Ferrin, 2002). McAllister (1995) conceptualized trust as a two-dimensional construct comprising affect-based and cognition-based trust. Affect-based trust is grounded upon emotional investments and expressions of genuine care and concern in trust relationships, whereas cognition-based trust is built upon attributions of the leader’s characteristics, such as ability, integrity, and reliability (McAllister, 1995). According to Colquitt, LePine, Piccolo, Zapata, and Rich *Correspondence to: Syed Akhtar, Department of Management, City University of Hong Kong, Hong Kong, Kowloon, Hong Kong. E-mail: mgsyed@cityu.edu.hk Copyright © 2013 John Wiley & Sons, Ltd. Received 01 June 2012 Revised 17 May 2013, Accepted 17 June 2013 Journal of Organizational Behavior, J. Organiz. Behav. 35, 373–392 (2014) Published online 26 July 2013 in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/job.1884 Research Article