Vassiliki, Baroness von Ruffin (born Vassiliki Papathanasiou, Greek: Βασιλική Παπαθανασίου, 23 August 1949 (disputed year of birth), known by her stage name Vicky Leandros, is a Greek singer with a long international career. She is the daughter of singer, musician, and composer, Leandros Papathanasiou (also known as Leo Leandros as well as Mario Panas). In 1972, she achieved worldwide fame after winning the Eurovision Song Contest with the song, "Après Toi", while representing the country of Luxembourg.

On 15 October 2006, Vassiliki von Ruffin was elected town councillor of the Greek harbour town of Piraeus on the Pasok list. Her task concerned the Cultural and International development of Piraeus. She was also Deputy Mayor of Piraeus. It was announced in June 2008 that Leandros decided to leave her position in Greek politics with immediate effect, stating that she had underestimated the work load and time needed to fulfill her political obligations and that it had become impossible to combine those duties with her singing career.