A critical challenge facing today’s organizational leaders is gaining their followers’ trust and having them view leaders as effective in addressing turmoil and change. Using a downsizing scenario as the context, this field experiment examined how a leader’s positivity and transparency impacted followers’ perceived trust, defined in terms of willingness to be vulnerable, and effectiveness of their leader. To test the hypotheses, 304 participants were randomly assigned to one of the four conditions of high (low) leader positivity × high (low) leader transparency. Results of our mixed methods study indicated both the leader’s level of positivity and transparency impacted followers’ perceived trust and evaluations of leader effectiveness. Besides limitations and suggestions for future research, we conclude with the practical implications that positive, transparent leaders may have on building trust and perceived effectiveness among their followers