From 1992 until 1995, Müntefering served as State Minister of Labor, Health and Social Affairs in the government of Minister-President Johannes Rau of North Rhine-Westphalia.

[4] Following Schröder's defeat in the close 2005 elections, Müntefering helped form a grand coalition under the new Chancellor Angela Merkel and her center-right CDU/CSU parties.

[6] Later in the day, Müntefering said that he would leave his positions in the government on 21 November attributing his decision to the illness of his wife, Ankepetra, who was suffering from cancer.

[7] Upon leaving office on 21 November 2007, he was replaced as Vice Chancellor by Frank-Walter Steinmeier and as Minister of Labor by Olaf Scholz, both of whom are also members of the SPD.

Following her death, Müntefering decided to return to active politics and was elected Chairman of the Social Democratic Party of Germany on 18 October 2008.

[17] In 2002, news surfaced that, while Müntefering was head of the SPD in the North Rhine-Westphalia during the 1990s, local officials in the city of Cologne and possibly elsewhere allegedly engaged in corruption that involved illegal political donations from builders of waste-disposal facilities.

Müntefering denied any knowledge of the anonymous donations and launched an internal investigation into all contracts awarded for the construction of waste-disposal facilities in North Rhine-Westphalia in the 1990s.