Rosa Diez is a Project Director within the Tunnels Division in Mott MacDonald Ltd. She started her career in underground construction over 23 years ago on the Heathrow Express project.  After participating in the design of the Channel Tunnel Rail Link and several projects overseas (Rome Metro, Asuncion Sewer and CERN) she was appointed as Geotechnical Lead for the supervising team of the Porto Metro (Portugal) during the construction. On her return to the UK, and working for Mott MacDonald Ltd, she took Design Manager roles for projects for London Underground (Waterloo & City Step Free Access and Victoria Station Upgrade) and in 2012 she joined the Crossrail team as Design Manager for the C121 contract where she was responsible for the detailed design of all the SCL stations, crossovers and other SCL structures in the project.  She also participates in Hydro Projects in South America and Spain as Tunnelling Expert and Expert Witness.