Born in Vienna, Austria, Marie-Thérèse Pictet-Althann completed her secondary education in Germany, followed by language studies in Fribourg (Switzerland), London and Vienna before joining the United Nations Office at Geneva in 1970 as an international civil servant. Following an assignment in the Division of Administration, she served the Office of the United Nations High Commissioner for Refugees from 1974 to 1983. During this period, she took on field missions to Africa and Central America and was entrusted in the Division of Protection with the reunification of refugee families, in particular those originating from Eastern Europe.

From 1984 to 1994, Marie-Thérèse Pictet-Althann accompanied her husband, François-Charles Pictet, on his assignments as Ambassador of Switzerland to the United Kingdom, the Netherlands, Austria and the Holy See and since 2022 to the Interparliamentary Union. In 1995, she joined the diplomatic service of the Sovereign Order of Malta where she has since served as First Counsellor, Minister Counsellor and Deputy Permanent Observer and since 2005 as Ambassador and Permanent Observer to the United Nations Office and other international organizations in Geneva.

In 1999, Marie-Thérèse Pictet-Althann founded the Diplomatic Spouses’ Circle, now the International Circle of Geneva, which she served as President until 2009. She was also Vice-President of the Geneva Diplomatic Club and served on its committee. In 2011 she co-founded with Cardinal Silvano Tomasi the Foundation “Caritas in Veritate” and served as its Vice-President until 2015. From 2005 to 2017 she was a member of the Board of the EORTC Cancer Research Fund (European Organization for Research and Treatment of Cancer, Brussels) and between 2013 and 2020 President and then Vice-President of the Geneva Association of Friends of the “Orchestre de la Suisse Romande”. She has been an International Gender Champion since the leadership network was launched in 2015 and represents the Order of Malta on the International Religious Freedom or Belief Alliance since 2020.

In 2002, she was awarded the Order of Malta’s Cross pro Merito Melitensi with Crown and in 2015 with Plaque. In 2022 she received the award of the Grand Cross of the Order of Malta. She became Dame Commander of the Papal Order of Saint Gregory the Great in 2014.