Employer branding has been advocated as an effective strategy for motivating employees to "live the brand" however, previous research has tended to focus on recruitment. As a result, little is known about what makes an organisation's employer brand attractive to its current employees. The objective of our study is to address this question through the lens of Social Identity Theory (SIT) which we do by conducting a comparative case study across four organisations. We found that the specific attributes considered most attractive by employees were different in each organisation. However the categories of attribute were almost identical; these were employment, organisational successes, construed external image, and product or service characteristics. We also argue that managers need to identify the attributes of their own organisation that employees find most attractive within these categories in order to link the employer brand with the identity of the organisation, and the interests of employees.