This paper describes the development and validation of the multi-dimensional Ethical Leadership at Work (ELW) questionnaire. Based on theory interviews and a student sample we developed seven ethical leader behaviors (fairness integrity ethical guidance people orientation power sharing role clarification and concern for sustainability). We then tested the factor structure in two employee samples (first common-source EFA; next multi-source CFA). To establish construct validity we related ethical leader behaviors to other leadership styles and employee attitudes in Study 1. The expected pattern of relationships emerged e.g. positive relationships with satisfaction and commitment and negative ones with cynicism. The results suggest that the ELW scales have sound psychometric properties and good construct validity. In Study 2 using a multi-source sample the ELW behaviors explained variance in trust OCB and leader and follower effectiveness beyond a uni-dimensional measure of ethical leadership. Ethical leadership was also related to OCB (supervisor-rated). Employees who rate their leader higher on power sharing and fairness show more OCB. Taken together the results suggest that the ELW is a useful new multidimensional measurement tool that can help further our understanding of the antecedents and consequences of ethical leadership.