Though the challenges and problems related to leadership in the public (government), private (business), and nonprofit sectors have some similarities, the unique nature of the nonprofit sector suggests that the application of management tools, such as a leadership competency model, if described and contextualized, might benefit nonprofit organizations. The purpose of this research study was to develop a new competency model for executive leaders of social service organizations in the nonprofit sector. The study also sought to compare these competencies with similar roles in other sectors to see if any differences could be articulated. The results of this study were not only a competency model crafted specifically for those leading social service agencies, but also a comparison with other competency models. The new competency model can be helpful in the recruitment and development of executive leaders in the nonprofit sector. It was developed with input from leaders, board members, and educators who have served and worked in nonprofits.