Koenigs was the human rights policy spokesman of the Bündnis 90/Die Grünen parliamentary group as of November 2013.

[1] From 1997 to 1999, Koenigs was the state executive spokesman of Bündnis 90/Die Grünen Hessen together with Sabine Giesa.

In this context, Koenigs is said to have been active in the cleaning group organized largely by Joschka Fischer in the early 1970s.

As head of the environment department, Koenigs played a leading role in the establishment of Frankfurt's green belt in 1991, the realization of which he retrospectively considers his greatest political success.

As deputy special representative of the UN Secretary-General in Kosovo, he was responsible for establishing the local civil administration.

In 2002 Koenigs was sent to Guatemala as a special representative to monitor compliance with the peace agreement by the former civil war parties as head of the UN peacekeeping mission MINUGUA.

In the 18th Bundestag Koenigs was the representative of his parliamentary group in the Committee on Human Rights and Humanitarian Aid and a full member of the Subcommittee on United Nations, International Organizations, and Globalization.