This document provides the railway operators, system integrators and product suppliers, with guidance and specifications on how cybersecurity will be managed in the context of EN 50126-1 RAMS lifecycle process. This document aims at the implementation of a consistent approach to the management of the security of the railway systems. This document can also be applied to the security assurance of systems and components/equipment developed independently of EN 50126-1:2017.All current amendments available at time of purchase are included with the purchase of this document.