Britney Spears' fianc Jason Trawick has been signed off as her latest conservator.

The singer's father Jamie Spears has had control over her affairs for the past four years but recently filed a petition to have Jason added as a co-conservator.

TMZ reports that the legal documents have now been put through the court system giving the Hollywood agent legal power over the millionaire starlet's affairs.

Jamie is said to be "thrilled" and believes it is in the best interest of Britney as she gears up to marry her beau.

"It's all in the family," his attorney Geraldine Wyle told reporters outside of the Los Angeles court.

Jason will help Britney decide on what jobs to take and how to spend her massive earnings which may include a $15 million pay day as the new judge on X Factor USA. But her father Jamie will still have the final say over her finances.

People magazine reports that Britney has lots of personal freedom and the conservatorship is mainly just a formality.

The conservatorship will only be lifted if a judge is advised by her doctors that she is well enough to handle her own affairs. It was initially put in place after her breakdown in 2008.