The doctor is Lord Alan Sugar's new business partner

Leah Totton has been crowned the winner of The Apprentice.

The NHS doctor beat rival Luisa Zissman, 25, to become Lord Alan Sugar‘s new business partner, securing a £250,000 investment for a chain of cosmetic clinics.

Leah, 24, shared her joy at scooping the prize on Twitter last night.

Yesssssssssssss!!!!!!!!!!!!! #theapprentice,’ she Tweeted after the news was announced.

Totally overwhelmed!!! O my god Iv won !!!! YESSSSS!!!!!! #TEAMLEAH #theapprentice #drleah

I am delighted to have won The Apprentice & to be @Lord_Sugar ‘s new business partner! Very excited for Dr Leah clinics and skincare range

New boss Lord Sugar, 66, also took to the site to congratulate his new colleague.

Very pleased to be entering into business with @DrLeahTotton – follow her for information and updates,’ the businessman Tweeted.

Fellow finalist Luisa might have failed to win Lord Sugar over with her baking brand but there were no hard feelings between her and Leah.

The pair have become close and Luisa says they’re now ‘lifelong friends’.

SEE PICTURES The Apprentice: Where are they now?

SEE PICTURES The Apprentice 2012: Meet the candidates – the have-a-go hero, the body-builder and the Blonde Assassin

SEE PICTURES The Apprentice 2011 – contestants revealed

Anna Francis