Ettlinger completed her doctorate in 1942 at the University of Basel,[1] having immigrated to Switzerland in the 1930s to escape Nazi Germany:[2] her thesis was published in 1949 as Die Keramik der Augster Thermen (Insula XVII).
[3] From September 1963 to June 1964, she was a member of the Institute for Advanced Study in Princeton, New Jersey.
[2][5] Her research centred on Roman ceramics such as Terra Sigillata, and she co-founded Rei Cretariae Romanae Fautores, a learned society dedicated to Roman pottery: she was its secretary, vice-president and then served as its president from 1971 to 1980.
[6] In 1972 she published Die römischen Fibeln in der Schweiz, which "still acts as an essential reference book for the study of Roman brooches.
After her father's death, she and her mother moved to Berlin, and then in 1935 to Switzerland to escape Nazi Germany.