Sienna Miller & Boyfriend Lucas Zwirner Attend Anna Wintour's Pre-Met Gala Dinner

Sienna Miller is all smiles while holding on close to boyfriend Lucas Zwirner as they leave Anna Wintour‘s townhouse on Sunday night (May 5) in New York City.

The 37-year-old actress sparkled in a black and gold dress while her 27-year-old boyfriend sported a black suit and white sneakers for the Pre-Met Gala dinner.

PHOTOS: Check out the latest pics of Sienna Miller

Sienna and Lucas have been linked to each other since earlier this year.

Lucas works for David Zwirner Books, the publishing house tied to his family’s art gallery. He is the editorial director and oversees 25 book releases a year.