Kostanza Dooku was a Human female hailing from the planet of Serenno. As a member of one of the Great Houses, she was part of the six most affluent noble families on her homeworld. She entered into marriage with the Count of House Dooku, who was the brother of the renowned Jedi Master Dooku. Following her husband's death, Kostanza Dooku acted as regent for their House. She remained in this role until her son, Adan Dooku, reached adulthood. However, around 32 BBY, her brother-in-law relinquished his position within the Jedi Order and assumed his family's title of Count. She and her brother-in-law were not on good terms.
Kostanza sought refuge on the planet Alderaan, residing there with her son until the older Dooku met his end during the Clone Wars. Upon reaching maturity, Adan inherited his uncle's title and governed as Count of Serenno until his assassination by the Galactic Empire in 3 BBY.
In Agent of the Empire – Hard Targets 2, Kostanza was mistakenly identified as the mother of Bron Dooku; the truth is she was his grandmother.