This presentation discusses: delivering a large-scale transport project (technical aspects and challenges); the benefits of a system engineering (SE) approach; the right "railway system"; the business case and customer focus; the SE approach to HS2 Phase 1 (the current place in the project development cycle, where this fits into the SE Vee lifecycle, the modelling performed, operations, traction power, tunnel ventilation, developing the operations and maintenance concepts, and requirements definition); and a brief description of key aspects of the Phase 1 railway systems design to date (a description of the route diagram, maintenance provisions, the Network Integrated Control Centre, integrated multifunctional sites and the tunnel ventilation system).