Bärbel Inhelder

Bärbel Elisabeth Inhelder (15 April 1913 – 17 February 1997) was a Swiss psychologist most known for her work under psychologist and epistemologist Jean Piaget and their contributions toward child development.

Born in St. Gallen, Switzerland, Inhelder initially showed interest in education. While attending high school she became interested in Sigmund Freud's writing and information on adolescents. She then moved to Geneva where she studied at the University of Geneva Institut Jean-Jacques Rousseau earning her bachelor's and doctoral degrees both in psychology. Inhelder continued her work at the University of Geneva up until her retirement. During her time at Geneva, she worked alongside Jean Piaget collaborating on experimental work targeted toward child development. Their collaboration began with her dissertation on children's conservation and continued for 50 years. Inhelder's work was significant in the discovery of the formal operational stage of child development occurring during the transition between childhood and adolescence. Inhelder and Piaget were joint on many publications of their research. Inhelder's contributions to developmental psychology resulted in her being elected as a Foreign Honorary Member of the American Academy of Arts and Sciences. Bärbel Inhelder died in 1997 of natural causes and her work is still used in developmental psychology today.