The Colas Group is the world leader in road construction and the railway division of Colas Rail and Seco Rail is one of Europe's leading providers of rail infrastructure services. In the UK Colas Rail Ltd combines the engineering skills of all our specialist businesses to provide total solutions in all aspects of railway infrastructure, from high speed rail systems to light and urban rail.

In May 2007 AMEC SPIE Rail changed its name to Colas Rail Ltd and an integrated management structure was formed embracing the activities of both Colas Rail Ltd and Seco Rail Ltd.

Colas Rail Ltd is a company with enormous history behind it. SPIE Rail has a century-long history of successful development in the wide sphere of railway engineering. The combination of the expertise found in both Colas Rail Ltd and Seco Rail Ltd will help make Colas Rail a major player in the UK rail industry.

SECO (Societe d'Etudes et de Construction d'Outillage) was set up in 1931 to build and operate the first mechanised ballast cleaning and levelling machine. In October 2000, SECO, renamed Seco Rail, became a wholly owned subsidiary of the Colas group, world leader in road construction, and has continued growing in the French and international markets, with subsidiaries in Belgium and the UK.

AMEC Rail was formed following the privatisation of British Rail. Initially a maintenance company specialising in the Southern region, the company developed and diversified. In 1999 a joint venture company was formed between AMEC and SPIE (AMEC SPIE Rail Systems Ltd). In 2001 AMEC purchased SPIE and new company was created - AMEC SPIE Rail Ltd. By early 2007 it had become both a project-based company with contracts across the UK and a freight operator.