Years ago employer branding was assumed to be a short-lived trend of human resource management but over the recent years it has become anchored in organizational management as a long-term and cross-departmental part of corporate strategy. Today more and more organizations are driven to implement an employer brand in order to compete in the labor market. But why do organizations see building an employer brand as important? What drives employer branding and how can the employer brand be measured? Does existing knowledge about the organization influence the evaluation of the employer brand? These and further questions are discussed on two different perspectives, the organization's and the target group's. Besides the development of a model describing the drivers of employer branding, an alternative scale measuring the external employer brand strength (EXEBS-Scale) is developed, validated and tested to explore the influence of selected constructs on the employer brand evaluation. Besides the scientific contribution to existing employer branding literature this book delivers new insights and specific recommendations for practitioners.