Länsimetro Oy is a limited liability company that is jointly owned by the cities of Espoo and Helsinki. Länsimetro Oy’s task is to build, own, maintain and develop the West Metro system, tracks and stations from Ruoholahti westwards. Phase one of West Metro, from Ruoholahti to Matinkylä was completed in October 2017. As the metro system and infrastructure owner, Länsimetro Oy’s task is to ensure that the West Metro’s metro system and its stations provide a safe commuting environment throughout their lifecycle. The second phase of the West Metro project, Matinkylä–Kivenlahti, involves the construction of seven kilometres of rail line and five new stations, and the construction of an underground metro depot in Sammalvuori. The rail line, stations, depot and metro system that are part of the second phase will also remain under Länsimetro Oy’s ownership. The construction phase covers the years 2019–2021, and commissioning is scheduled for 2022–2023.