This article explores the obligation of Member States, under Article 19(1) TEU, to uphold the judicial independence of all national courts who ‘may’ rule on Union law. The European Court of Justice (ECJ) first set out this obligation in their seminal ruling in Associação Sindical dos Juízes Portugueses and has since developed an extensive case-law. This article explores and discusses that case-law with the purpose of setting out, in a general manner, the key obligations Member States have under Article 19(1) TEU. Furthermore, where the ECJ has only set out general requirements without detailing their content, this article expands on the case-law by supplementing and contrasting solutions provided to similar issues in the case-law of the European Court of Human Rights (ECtHR), the recommendations of the Venice Commission and in wider International Human Rights Law. Finally, this article discusses whether judicial independence can be balanced against other aims, concerns and goals, and what room that leaves Member States to justify potential restrictions on judicial independence by the pursuit of (other) legitimate objectives.