This paper aims to investigate the role of empowerment on employee performance in petroleum industry - EMS department- in order to improve the application of the EMS ISO 14001.
The study addresses two perspectives of empowerment (i.e., structural and psychological). Research population three hundred and seventy-seven questionnaires. Findings reveal that both forms of empowerment have a positive and significant impact on employees' performance. However, psychological empowerment has a stronger impact on employees' behavior than does structural empowerment.  Three dimensions of structural empowerment (communications, training, and knowledge and skills) have a significant positive impact on the dependent variable. In addition, three dimensions of psychological empowerment (meaning, competences and impact) have significant and positive impacts on employees' performance. This study offers new insights into the existing literature and provides implications and directions for future research.