Catarina is the Executive Chair of Sanitation and Water for All (SWA) global partnership, which has the objectives of achieving universal access to clean water and adequate sanitation for all, always and everywhere. She was the first United Nations (UN) Special Rapporteur on the right to safe drinking water and sanitation (2008-2014), having played a pivotal role in the recognition of water and sanitation as human rights by the UN General Assembly in 2010. Between 2004 and 2008 she successfully chaired the negotiations of the UN Optional Protocol to the International Covenant on Economic, Social and Cultural Rights, which was approved by consensus by the UN General Assembly.

Catarina has been awarded the Portuguese Parliament Golden Medal for her work in the area of human rights and was honored by the Portuguese President with the Order of Merit for her work on human rights. She has chaired several negotiations at the United Nations in the areas of child rights and economic, social and cultural rights in representation of her own government and of the European Union. She has taught in several European and American universities and has been a consultant in the area of human rights for several European and UN agencies.