The main construction of HS2, Britain's high-speed rail network, began in September 2020. Phase One will see London to Birmingham linked by trains that can reach 225mph and Phase Two joins Birmingham with Manchester and Leeds. With Phase One consisting of 140 miles of track, 32 miles of tunnels and 10 miles of viaducts, HS2 is the UK's largest ever railway infrastructure building project. These two volumes contain a collection of papers submitted to HS2's Technical Papers Competition, detailing the key infrastructure and design aspects considered for the HS2 Project. Contributions have come from consultants, contractors, suppliers and third-party stakeholders from some of the largest engineering firms. The papers showcase the skills of the personnel involved and the successful delivery of each phase of works. This two volume set examine the challenges of this unprecedented project and learning in planning, design, construction and management for major railway infrastructure projects. It will interest any engineer or professional desiring critical information on the design and build of HS2.