Growing up in Switzerland, Tatiana attended Paris boarding school Lycée Fontainebleau and is known for being a skilled linguist. Later, she studying the history of Art at the American University of London. She speaks five languages fluently: English, Portuguese, Spanish, Italian, and French. She created the ethical retail portal Muzungu Sisters with business partner Dana Alikhani, which she has used as a platform to champion fair trade artisan garments. Their brand has been supported by other socialites, such as Eugenie Niarchos, Margherita Missoni and Gaia Repossi.
She is currently engaged to Andrea Casiraghi, the eldest son of Caroline, Princess of Hanover, and second in the line of succession to the Monegasque throne. She first met Andrea at her boarding school in Paris and started dating him in 2004. They are planning for a wedding in 2013.
Tatiana Santo Domingo is also a supporter of various charities, including the Motrice Foundation.