The Made In Chelsea star joined her BFF Millie Mackintosh at the Pretty Ballerinas spring/summer '15 launch, held at Mexican restaurant La Bodega Negra.
Rosie is known for her chic sense of style and love of tailoring, and she got things spot on with her latest fab ensemble.
The starlet showed off her slender pins in a pair of skin-tight leather trousers, which she teamed with a white shirt featuring black piping and a cute Peter Pan collar.
She added a navy blazer over the top, while giving her getup a feminine touch with suede cobalt blue heels complete with perspex panels.
On the beauty front she opted for a natural yet glossy look, styling her golden brunette strands in soft waves which tumbled past her shoulders.
Her make-up was pared-back and simple with just a slick of mascara defining her blue peepers, along with a light dab of pink on her cheeks and glossy lips.
But the best part of her look? It had to be her super-fancy arm candy, of course!
Rosie has a closet packed with designer bags (jealous!) but this time chose a beautiful pink tweed number by Chanel.
Isn't it just gorgeous? We want one!
What do you think of Rosie's outfit? Let us know by commenting below as the best comment across the site each week wins £50!
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