"Women actually come up to me and show me their bras," she says. "I get tweets and texts, and people will Instagram what they're wearing, and it's women of all shapes and sizes and ages, and that makes me very proud."
Despite her successes as both a model, designer and actress, Rosie claims it's not down to luck.
Her interview with the magazine is teamed with a glamorous 12-page shoot, photographed by David Slijper.
How does she look? In her element and dressed in statement designer pieces from Donna Karan, Stella McCartney and Saint Laurent.
Want to read more? The September issue of Harper's Bazaar is available on newsstands on August 5.
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