| Crossrail is a complex programme to provide new rail services between Reading and Heathrow west of London and Shenfield and Abbey Wood. It includes a new underground railway beneath central London. |
| The Department and TfL are sponsoring and funding Crossrail jointly. The sponsors expect the railway to reduce congestion, increase capacity, reduce journey times and enable economic growth. |
| Crossrail Ltd is responsible for delivering the programme, from building the line and stations, through to integrating systems and providing an operational railway. Crossrail Ltd is a company wholly owned by TfL with an independent board. |
| During 2018 sponsors and Crossrail Ltd made a series of announcements about significant cost increases and delays to the programme. |
| It remains unclear when the central section of the railway will open, with Crossrail Ltd having missed its target to open this section in December 2018. Crossrail Ltd does not yet have a firm estimate of the revised cost to complete the programme. |