Although the value of a supportive organizational climate has been recognized over the years, there is a need for better understanding of its relationship with employee outcomes. This study investigates whether the recently emerging core construct of positive psychological capital (consisting of hope, resilience, optimism, and efficacy) plays a role in mediating the effects of a supportive organizational climate with employee outcomes. Utilizing three diverse samples, results show that employees' psychological capital is positively related to their performance, satisfaction, and commitment and a supportive climate is related to employees' satisfaction and commitment. The study's major hypothesis that employees' psychological capital mediates the relationship between supportive climate and their performance was also supported. The implications of these findings conclude the article. Copyright © 2008 John Wiley & Sons, Ltd.