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All Black Everything
Jess looks mature, sleek and über-blond in her all-black blazer, slim-fit legging and suede bootie combo.
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Jamie McCarthy/Getty Images
Chicago Sparkles
Sparkling in this long-sleeve silver sequin mini with blinged-out earrings, Jess could steel the show at younger sister Ashlee Simpson-Wentz's premiere of Chicago.
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AP Photo/Peter Kramer
Classy Cute
Jess shows her class and sass in this tank-style black mini with cinched waist and sparkling peep-toe pumps.
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Business Class
If there was ever a way to make an androgynous vest suit sexy and fem, Jess does it at Operation Smile's 8th Annual Gala.
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KEVIN DIETSCH/UPI /Landov
Sexy Stripes
Looking busty and all-American in this red and black striped number with tan wedges and gold Chanel hoops, we can't blame our servicemen for being a tad distracted.