The Oscar-winning actor and her writer husband Andrew Upton have signed on as co-artistic directors of the Sydney Theatre Company (STC), starting in January 2008.
"The acceptance for the role of co-artistic director of this company is not a dalliance," Blanchett told reporters in Sydney today.
"It's an absolutely firm commitment and it is not one that Andrew nor myself have made lightly."
Blanchett and Upton will replace Robyn Nevin, who will leave her post after eight-and-a-half years.
The married couple will write and act with the company as well as steering its programming.
Blanchett said it would be a full-time job, although there would be three months a year in which she and her husband could devote to their own creative projects.
"As artistic director there is a three month slot a year and sometimes I may take that up and sometimes I may not," Blanchett said.