Düwag or Duewag (stylised in all caps), formerly Waggonfabrik Uerdingen, was a German manufacturer of rail vehicles.

In 1981, the company changed its name from Waggonfabrik Uerdingen to Duewag.

[1] Siemens acquired a 60% shareholding in 1989 before taking full ownership in April 1999.

[2][3] In 2001, the Düsseldorf plant was closed with production transferred to Uerdingen.

[4] Duewag vehicles were close to a monopoly market in West Germany, as nearly every tram and light rail vehicle purchased from the 1960s onward was built by Duewag.