[5] After the resignation of party leader Björn Engholm in 1993, she stood for the Social Democrats' candidacy for the chancellor's office,[6] but lost to Rudolf Scharping.

From 1993 to 2005, Wieczorek-Zeul served as deputy chairwoman of the SPD, under the leadership of successive chairmen Rudolf Scharping (1993–1995), Oskar Lafontaine (1995–1999), Gerhard Schröder (1999–2004) and Franz Müntefering (2004–2005).

From 2009 to 2013, Wieczorek-Zeul served on the Bundestag’s Committee on Foreign Affairs and as spokesperson of the SPD parliamentary group on the Subcommittee on the United Nations, International Organizations and Globalization.

[12] In October 2001, she joined Schröder on a state visit to Pakistan for meetings with President Pervez Musharraf, where they revived economic assistance to the country in return for its support for the U.S.-led campaign against terrorism and in light of incoming refugee flows from Afghanistan.

On 26 January 2009, Wieczorek-Zeul and Environment Minister Sigmar Gabriel chaired the conference which led to the founding of the International Renewable Energy Agency (IRENA).

Role in international organizations After Merkel formally launched the World Bank Group’s three-year Gender Action Plan in February 2007, Wieczorek-Zeul served as honorary co-chair (alongside Danny Leipziger) of the High Level Advisory Council on Women's Economic Empowerment and as Official Champion of the World Bank Group Gender Action Plan.

[27] Alongside Chancellor Merkel, Wieczorek-Zeul co-hosted the Global Fund to Fight AIDS, Tuberculosis and Malaria replenishment conference in Berlin in September 2007.

[29] In 2008, Wieczorek-Zeul served as Special Envoy of the UN Secretary-General Ban Ki-moon for the International Conference on Financing for Development in Doha, Qatar.

[31] Also between 2008 and 2009, Wieczorek-Zeul served as member of the Commission of Experts of the President of the UN General Assembly on Reforms of the International Monetary and Financial System, which was chaired by author and Nobel Laureate economist Joseph E. Stiglitz.

[32] Since leaving politics, Wieczorek-Zeul has been involved in a number of philanthropic activities, including the following: In 2001, Wieczorek-Zeul called for 39 pharmaceutical firms – including GlaxoSmithKline, Merck, Bristol-Myers Squibb, Roche, and Boehringer Ingelheim – to abandon their legal challenge to a South African law designed to lower the price of patent-protected HIV and AIDS medicines.

In a joint statement with Health Minister Ulla Schmidt, she criticized the pope's remarks and underlined the importance of condom use in developing nations.

In May 2008, Wieczorek-Zeul was the only minister of Chancellor Merkel’s government who agreed to meet with the Dalai Lama, the spiritual leader of Tibet, during a five-day visit to Germany.

[49] The visit took place eight months after a historic meeting between the Dalai Lama and Merkel caused a deep diplomatic rift between China and Germany.