Railtrack was a group of companies that owned the track, signalling, tunnels, bridges, level crossings and all but a handful of the stations of the British railway system from 1994 until 2002. It was created as part of the privatisation of British Rail, listed on the London Stock Exchange, and was a constituent of the FTSE 100 Index. In 2002, after experiencing major financial difficulty, most of Railtrack's operations were transferred to the state-controlled non-profit company Network Rail. The remainder of Railtrack was renamed RT Group plc and eventually dissolved on 22 June 2010.

During the early 1990s, the Conservative Party decided to pursue the privatisation of Britain's nationalised railway operator British Rail. A white paper released in July 1992 had called for a publicly owned company to be primarily responsible for the railway infrastructure, including the tracks, signalling, and stations, while train operations would be franchised out to various private companies. However, Robert Horton, who would become the first chairman of Railtrack and thus play a leading role through the early years of the organisation's existence, lobbied for the infrastructure-holding company to be privatised as well in order to maximise financial gains; this position was also supported by several figures within the Conservative government, such as the Chancellor of the Exchequer Kenneth Clarke and the Secretary of State for Transport Brian Mawhinney.

On 1 April 1994, in accordance with recently passed legislation, the newly established Railtrack took control of Britain's railway infrastructure from British Rail. Its primary revenue sources were the track access charges levied on train operators and the lease of stations and depots. Furthermore, the company routinely received funding from the British government; the resulting money was largely spent on the railway network in accordance with plans laid out by the rail regulator. Between its creation and late 1998, the company reportedly had a relatively calm relationship with its first economic regulator, John Swift QC, who exercised a strategy of encouraging Railtrack to make its own commitments towards improvement. According to the railway historian Christian Wolmar, the regulator had intentionally acted weak as to avoid complicating the creation and privatisation of Railtrack.

In January 1996, the British government confirmed its plans to privatise Railtrack for £2 billion with a total asset value of £4 billion. During May 1996, the company was floated on the London Stock Exchange, albeit at a lower than planned price, allegedly in response to a threatened intervention by the Labour Party. This action effectively privatised Railtrack, although the company remained closely intertwined with the British government from an operational standpoint.

Railtrack's initial operations were disrupted by an industrial dispute that largely ran between June and September 1994; at one point, the company's management proposed dismissing all of its signallers, comprising roughly 4,600 staff. Railtrack's first chief executive, John Edmonds, pursued a strategy of disposing of engineers and outsourcing their work wherever possible with the goal of reducing costs. Within its first few years of operation, Railtrack appeared to perform well financially, annual profits were recorded while its share value quadrupled within a relatively short timeframe. Furthermore, during the mid-to-late 1990s, several high-profile investment projects in cooperation with train operators and other partners were announced by the company. However, as early as 1997, Railtrack was being criticised for paying little attention to infrastructure investment.

The Southall rail crash in 1997 and the Ladbroke Grove rail crash in 1999 called into question the negative consequences that the fragmentation of the railway network had introduced to both safety and maintenance procedures. Railtrack was severely criticised for both its performance in improving Britain's railway infrastructure and for its safety record. It was observed in Lord Cullen's inquiry into the Ladbroke Grove accident that trains would have been prevented from passing any signal at red had an Automatic Train Protection (ATP) system had been fitted and operational; however, ATP's national adoption, a recommendation made after the Clapham Junction rail crash in 1988, had been abandoned as the cost was considered to be excessive for the increase in safety.

One particular area of criticism was that the regulator was not tough enough on Railtrack and, as a result, the company had been able to abuse its monopoly position. In particular, Railtrack's customers, the passenger and freight train operators, were allegedly desperate for regulatory action to compel the company to improve its stewardship of the network and its performance. During 1993, Swift had been appointed rail regulator by the then Conservative transport secretary John MacGregor MP. When the Labour government took over after the general election in May 1997, the new transport secretary (and deputy prime minister) John Prescott took a much harder line. When Swift's five-year term of office expired on 30 November 1998, he was not reappointed.

After an interim period, during which Chris Bolt, Swift's chief economic adviser and effective deputy, filled the regulator's position, in July 1999 a new rail regulator began a five-year term, starting a much tougher regulatory era. Tom Winsor, the new rail regulator, had been Swift's general counsel (1993–95), and adopted a more interventionist and aggressive regulatory approach. The relationship between the two parties was reportedly stormy at times; in April 2000, it was reported in The Guardian that "Railtrack is adopting a deliberate 'culture of defiance' against the rail regulator". Gerald Corbett, Railtrack's chief executive at the time, and Winsor did not share the same vision for the network. Railtrack resisted regulatory action to improve its performance, and as the regulator probed ever more deeply, serious shortcomings in the company's stewardship of the network were revealed. Winsor informed Railtrack that if it did not improve passenger train performance by 12.7 per cent by March 2000, the company would have to pay fines out of its profits.