This commentary provides an expert article by article guide to the The Digital Markets Act and its application. The Digital Markets Act (DMA) is the European project for regulating digital gatekeepers. The DMA is the first encompassing legislative set of rules that goes beyond traditional competition law and provides essential rules for doing business with digital gatekeepers, in response to the global recognition of the need for increased regulation of the sector. This volume explores who, as "digital gatekeeper", is the direct addressee of the prohibited conduct, how the obligations must be implemented, what rights the commercial users of the platforms are entitled to, and how to proceed in the event of a violation against gatekeepers. All lawyers practising in the digital market sector will find this an invaluable resource.