Christina Hendricks Birthday: 'Mad Men' Star Turns 37, Her Best Red Carpet Looks [PHOTOS]

With Mad Men finally back on AMC after its long hiatus and Joan Holloway back at Sterling Cooper Draper Pryce, Christina Hendricks is having a great year.

The Knoxville-born actress has even more to celebrate on Thursday, as she turns 37 years old.

Since hitting all the right notes on the Mad Men pilot some five years ago, Hendricks has taken on several film projects, including a small role in Life as We Know It (opposite Katherine Heigl and Josh Duhamel), Detachment (opposite Adrien Brody) and Drive (opposite Ryan Gosling).

Through it all, the gorgeous redhead has maintained a healthy and strong relationship with her husband of nearly three years, actor Geoffrey Arend (Body of Proof).

It's incredibly flattering and surprising, and I didn't think for a second when I started 'Mad Men' that people would talk about me as being sexy or a pin-up, Hendricks said of all the attention devoted to her curves, in the March issue of Cosmopolitan UK.

My husband has a good laugh about it, of course, she added.

Hendricks, who has turned heads at just about every red carpet she's walked, also told Cosmopolitan that sexiness is about confidence and individuality. I can't keep my eyes off the women you see in cities like London, New York and Paris -- the way they carry themselves and put themselves together are always so unique.

According to that definition, Hendricks is not so bad herself.

In celebration of Christina Hendricks' 37th birthday, click through for some of her best red carpet looks.

The next episode of Mad Men airs on Sunday, May 6 on AMC.