06/22/2012 04:16 pm ET Updated Jun 22, 2012

Meryl Streep's Best On-Screen Style (PHOTOS)

As one of the greatest actresses of all time (yep, we said it), Meryl Streep is a magical on-screen chameleon, transforming into characters as different as Miranda Priestly and Julia Childs with utter effortlessness.

But there is some behind-the-scenes effort involved... on the part of the costume designers, at least. The age-old saying "the clothes make the (wo)man" was never truer when Meryl slipped into Maggie Thatcher's skirt suits, Senator Shaw's power blazers or, yes, Miranda Priestley's luxe Prada duds. And Meryl owned every single look.

So to celebrate Streep's 63rd birthday today, we're taking a look back at the actress' most memorable on-screen looks. Which is your favorite? Vote in the slideshow below.

Meryl Streep's Best On-Screen Fashion