Persistent left superior vena cava (PLSVC) is a congenital variant of the thoracic venous system, which is associated with other congenital abnormalities. Asymptomatic cases are often diagnosed incidentally during invasive cardiovascular procedures such as the deployment of central venous access devices. It is important to be aware of the existence of a PLSVC and the clinical implications that it may pose to the proceduralist during catheter placement. We describe our experience and the lessons learnt during the placement of a haemodialysis catheter via the left internal jugular venous route in a patient with unsuspected PLSVC.