The Digital Transformation of Metros study reviewed the strategies, initiatives, and technologies used by metros to implement digital transformation for four key purposes: safety improvement, station operations and management, train operations, and depot management. In recent years there have been several digital trends observed in metros, including provision of real-time train loading information, centralised station management, customer-facing staff equipped with tablets, installation of passenger counting equipment, etc. Metros’ long-term digital transformation plans typically involve multi-phase programmes with strong support from management, employee expertise, and partnership with external parties. Ultimately, digital transformation is highly related to transforming employees. Therefore the study summarised metros’ good practices to create a digital culture, as well as ways to remove barriers along the journey to digital transformation.