Sienna Miller Loves Matthew Williamson

Sienna Miller attends designer Matthew Williamson‘s bar party at London’s St Martins Lane Hotel on Wednesday night.

The 26-year-old actress dressed in a bright green Williamson dress, funky necklace, black tights and black flats. Sienna left the party with pal Rhys Ifansand ended the night at Groucho Club.

10+ pictures inside of Sienna, Mathew and Rhys…

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