Awards season is upon us once again! The 2013 American Music Awards took place Sunday night at the Nokia Theater in Los Angeles, California. Rapper Pitbull hosted the show, which featured headlining performances by Justin Timberlake, Miley Cyrus, One Direction, Jennifer Lopez, and Rihanna. Several of the performers were also named winners; Rihanna for Favorite Female Artist, Soul/R&B, One Direction for Favorite Band, Duo or Group, Pop or Rock, and Justin Timberlake for Favorite Album, Soul/R&B ("The 20/20 Experience"), Favorite Male Artist, Soul/R&B, and Favorite Male Pop Rock Artist. Also of great note, Taylor Swift was chosen for Artist of the Year (in addition to two other awards). The red carpet also had its own winners... as well as its own losers. Here are the Best and Worst Dressed for the 2013 American Music Awards.

Best

5. Kendall Jenner

and

4. Kylie Jenner
You have to admit that these girls looked great. The teenage sisters both opted for sexy modern silhouettes that are still pretty age appropriate. Kendall wore a keepsake mini dress, while Kylie wore a Maiyet top and Giambatista Valli pants. Both finished their outfits with some killer pointy shoes.

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3. Katy Perry
While some people could end up on the Worst Dressed list with this gown, quirky Katy Perry looks amazing in this polka dotted Oscar de la Renta. The embroidered flowers are a sweet little vintage-y touch. So adorable!

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2. Taylor Swift
T-Swift looked so glamorous in this fun metallic mini dress by Julien Macdonald. The short length and cutout on the bodice were sexy little touches, but still kept it classy. Matching strappy gold Jimmy Choos finished off the dazzling look.

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1. Naya Rivera
This star sure knows how to do classy cleavage. Rivera's black Michael Kors gown is perfectly balanced with an extremely flattering fit, a revealing keyhole, and more modest long sleeves. Naya finished the look with the perfect hairstyle and some gorgeous gold statement jewelry. The train on this dress ups the glamor factor as well.

Worst

5. Heidi Klum
Heidi can do so much better than this! This lacy black Marchesa is gorgeous from the waist up, but that long fringed skirt is appalling. It's like a black stringy hula skirt! I'm going to have to give her props for those fabulous Brian Atwood heels though.

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4. Jennifer Hudson
If you thought you couldn't go wrong with Dior, you'd be wrong. It looks like Jennifer Hudson made that mistake when selecting this bright orange and pink dress. The top half looks like a plain old t-shirt, and the skirt looks as if someone started making the dress into a mini, but didn't finish cutting it all the way around.

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3. Aubrey O'Day
Danity Kane's Aubrey O'Day was overexposed, to say the least, in this bright red Ryan Jordan dress. Too much cleavage and too much leg. This almost looks like a slutty Halloween costume. Just add the devil horns and a pitchfork.

2. Kelly Osbourne
What would Joan Rivers say? Kelly Osbourne may be a critic on Fashion Police, but she deserves a major violation for this unflattering prom dress by Rami Al Ali. The boxy basket weave on top combined with its stiff straight tulle skirt and odd length make it one of the worst dresses of the night. Are the purple bangs helping? Not so much, Kelly. Not so much.

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1. Lil' Mama
Attention Lil' Mama: Your hair does not have to match your dress. And if your dress has green accents, your hair definitely shouldn't match. This dress on its own is bad enough, with its odd not quite peplum shape and overly large embellishment, but top it off with a green bob, and you've got a real mess. This outfit needs some TLC.

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