She is noted for her service with international aid and peacekeeping missions; a 2003 profile in the monthly magazine of the Neue Zürcher Zeitung called her "Switzerland's outstanding diplomat".
Returning to Switzerland in 1999, she was appointed head of Human Rights and Humanitarian Policy in the Department of Foreign Affairs.
[4] After a stint as Personal Representative of the OSCE Chairperson-in-Office for the Caucasus from 2000 to 2001, Tagliavini served as Swiss Ambassador to Bosnia and Herzegovina from 2001 to 2002,[4] and was asked by UN Secretary-General Kofi Annan to head UNOMIG in 2002.
The final report, published on September 30, concluded that Georgia had started the war, but that both sides were responsible for the escalation of the conflict.
[6] Tagliavini was until June 2015[7] a member of the Trilateral Contact Group on Ukraine, which was organized to attempt a diplomatic resolution to the conflict.