Langen first became a Member of the European Parliament in the 1994 elections. Throughout his time in office, he served on the Committee on Economic and Monetary Affairs. In this capacity, he was in charge of steering key financial reforms through the European Parliament, including the European Market Infrastructure Regulation (EMIR)[1][2] and the Insurance Mediation Directive (IMD 2) in 2015.[3] In July 2016, Langen was elected to chair the Parliament's Committee of Inquiry into Money Laundering, Tax Avoidance and Tax Evasion (PANA) that investigated the Panama Papers revelations and tax avoidance schemes more broadly.[4]
Between 2006 and 2012, Langen chaired the CDU/CSU delegation to the European Parliament. In this capacity, he once again served as a member of the CDU executive board, this time under the party's then chairwoman, ChancellorAngela Merkel. In 2010, he was a CDU delegate to the Federal Convention for the purpose of electing the President of Germany.
From 2014 until 2019, Langen was a member of the European Parliament Intergroup on Biodiversity, Countryside, Hunting and Recreational Fisheries.[6]