We round up the most memorable celebrity fashion looks from the week, from Michelle Obama's canary yellow Prabal Gurung gown to Kate Middleton's blue L.K. Bennett dress to Kaley Cuoco's dramatic flower tiara. We wish we had them all...

Celebrity fashion round-up: from Kate Middleton to Kate Mara

Nina Dobrev

Elisabeth Moss

Marion Cotillard

Reese Witherspoon

Kate Mara

Alessandra Ambrosio

Katie Holmes

Melanie Brown

Taylor Swift

Megan Fox

Gizzi Erskine

Catherine Duchess of Cambridge

Michelle Obama

Diane Kruger

Rosie Huntington-Whiteley

Jessica Alba

Christina Hendricks

Daisy Lowe

Cate Blanchett

Celebrity fashion round-up: from Kate Middleton to Kate Mara to Michelle Obama