Government support to producers of rolling stock is raising concerns about possible market distortions and unfair competition. This report aims to quantify both the scale of government support and to identify the various ways in which governments have been supporting local rolling-stock producers at the expense of foreign competitors. Over the period 2016-20, governments provided about USD 5 billion to the sector, much of it in the form of government grants and income tax concessions. While not quantified, discriminatory practices in government procurement and competition enforcement, forced technology transfers, as well as non-market export credits may have also distorted global competition in the rail-supply industry. Similar to earlier OECD studies of government support in the aluminium and semiconductor value chains, this report helps shed light on the magnitude and ways in which governments subsidise the producers of materials and equipment they view as strategic, with a view to informing efforts to revisit global trade rules.