Nanne graduated from the University of Amsterdam.
Dekking has held many distinguished positions. He began his career as assistant curator of the Historical Collections of HM The Queen of The Netherlands. He also spent some time as deputy administrative director of the Dutch National Ballet. From 1996 to 2001 Dekking and art consultancy firm and gallery in New York called Nanne Dekking Fine Arts. Later, he became vice president of Wildenstein and Company where he advised individuals, museums and foundations on their collections.
Dekking then leveraged his intimate relatinoship with collectors and museums to become vice chairman and the worldwide head of private sales at Sotheby's. In 2016 Dekking founded Artory in a bid to improve the art market for buyers, sellers, and appreciators.