The growth in multilateral working relationships (e.g. agency work, chains of sub-contracting and corporate groups) is causing Member States to increasingly scrutinise their traditional, contractual approach to the notion of ‘employer’. So far, little attention has been paid to the boundaries and limits that EU law sets when defining the employer. The lack of attention may have come to an end with the recent AFMB judgment, in which the Court ruled, for the first time, that the concept of employer in a provision of EU law had to be given an autonomous and uniform interpretation throughout the EU. Starting from the AFMB judgment, the author analyses the concept of employer in EU law. The author finds that the concept of employer in EU law can be described as ‘uniform in its functionality’: in EU law, the national concept of the employer is never absolute, but the circumstances and the way in which the national concept must be set aside depend on the context and the objective of the European legislation in question. Through this functional approach, EU law partly harmonises the various national approaches to the concept of the employer. Nevertheless, a lack of specific reasoning on the part of the Court may grant the Member States considerable leeway to uphold their own views on the concept.

多边工作关系（例如，代理工作，分包链和公司集团）的增长正在促使会员国越来越多地审查其传统的，以合同为基础的“雇主”概念。到目前为止，很少有人关注欧盟法律在定义雇主时设定的界限和限制。AFMB最近的判决可能已结束了对注意力的忽视，在该判决中，法院首次裁定，必须在整个欧盟范围内对欧盟概念中的雇主概念进行自治和统一的解释。从AFMB开始判决后，作者分析了欧盟法律中雇主的概念。作者发现，欧盟法律中雇主的概念可以被描述为“功能上的统一”：在欧盟法律中，雇主的国家概念绝不是绝对的，但是必须确定国家概念的情况和方式除了取决于相关欧洲法规的背景和目标。通过这种实用的方法，欧盟法律在某种程度上协调了雇主概念的各种国家方法。然而，法院缺乏具体的推理可能会给会员国留下很大的余地，以维持其对这一概念的看法。