Olivia Palermo headed out this week for a birthday bash, donning a ridiculously cute pair of polka dot pants for the occasion. We're fairly certain Olivia has access to any designer labels of her choice, but we love that she prefers to pair her expensive duds with stores the rest of us folk like to shop at -- like Banana Republic, for example.

Banana Republic has been seriously stepping it up lately with the designer collaborations. In stores right now is the new Marimekko line. Sound familiar? We're certain you've seen one of Marimekko's iconic prints before, and teamed up with a few of Banana Republic's classic, most-loved styles (like the signature Hampton pant), it's no surprise the collaboration is being snapped up left and right by celebs. Ashley Greene was spotted recently in a Banana Republic x Marimekko top, and Jamie Chung is apparently a fan as well.

Styled with a military-inspired jacket, a white sweater, and chic little black flats, Olivia has mastered an elegant high-low mix once again. Olivia's Hampton Pant in the Marimekko 'Kivet' print is sold in select Banana Republics -- head on over to your local store quick, before they're all sold out! You can shop the rest of the collection online.