ANSALDO STS is the leading technology group operating in the railway and underground transportation sector. In particular, it controls Ansaldo Signal N.V., a Dutch holding company which is the largest of a group of companies operating in the field of railway and underground signalling as well as Ansaldo Trasporti-Sistemi Ferroviari S.p.A., an Italian company, expert in IT systems integration in the area of "turnkey" railway and underground transport systems.

The activities of the ANSALDO STS Group are organized into two business units:

- the Signalling Unit which works in design, realization, management and maintenance of systems, subsystems and components for signalling and monitoring railway and subway traffic systems, aimed at increasing the safety and efficiency of railway and underground transport systems

- the Transport System Unit which operates in the design, realization, installation, integration, management, operation and maintenance of "turnkey" railway and underground transport systems among which signalling systems are an essential part

The Group's head office is in Genoa, and Ansaldo STS has company branches located in 18 countries with over 3,600 employees. In 2005, the group realized profits amounting to 840 million euros with a gross operating margin of 89 million euros and a net profit of 44 million euros.