Cary Fink was born on 26 September 1883 in Mexico City to American parents. She studied at Vassar College, graduating in 1906, and went on to earn a medical degree from Johns Hopkins University in 1911, though she never entered clinical practice. Her first marriage, to the folklorist and physician Jaime de Angulo, ended in divorce, and in 1921, at the suggestion of a teacher from her Vassar years, she traveled to Zurich to study with Carl Jung, becoming part of the small circle of analysts and translators who gathered around him in the years his psychology was first taking organized shape.
In 1925, at a Jungian conference in England, she met Jung's close associate Helton Godwin Baynes, known to friends as Peter; they married in 1927 and settled first in England before relocating to California in 1928. Under the name Cary F. Baynes she went on to translate several of Jung's own major works into English, including Contributions to Analytical Psychology and Modern Man in Search of a Soul, becoming one of the primary channels through which Jung's German language writing first reached English readers. She remained intellectually active until her death in October 1977.
Her medical training, though never put to clinical use, gave her an unusual scientific grounding among Jung's early circle of largely literary and philosophical translators, and Jung himself is reported to have valued her combination of precision and patience with difficult, layered source material. From her California home in her later years she continued corresponding with scholars using her translations and remained a point of reference for questions about Wilhelm's German and Jung's own idiosyncratic vocabulary until her death in 1977.