Are you one of the few blessed with the perfection that is an oval face? Longoria Parker is. While we applaud her creativity and experimentation with hairstyles, this look missed the mark. The risk for oval faces lies in fussy over-worked styles that detract from the wearer's beauty. This medium-length style is too busy and looks like one light breeze will mess it up. If you have an oval face, go for simplicity. Your face will thank you for it.

There's nothing quite as appealing as an oval face lightly framed by sexy, beachy waves. Jessica Biel proves the point in flying colors here. This medium-length hairstyle lets Biel's face take center stage with casual, unfussy waves and long, sexy bangs draped seductively across the forehead. A center part works great, too, if you want to be a little more understated.

While this is a terrifically chic hairstyle, it won't work on an oblong face. It's far better suited for square faces. The center part and long face-hugging sides go a long way to emphasize a long skinny face and high forehead. If you want your face to look even longer and skinnier, this is the medium-length hairstyle for you.

What a difference volume makes. This medium-length hairstyle creates the illusion of having the highly desirable oval face shape. Volume at the sides creates the illusion of fullness at the cheekbones. Bangs lightly dancing on the forehead reduce its dominance. Plus, we're pretty sure this look is the definition of "great hair."

We're not sure why Knightley would want to hide her stunning good looks with this afterthought of a hairstyle. But take it from us, if it doesn't look good on her, it almost certainly isn't going to look good on any of us. Hair that's above the shoulder needs to be kept simple and neat. These almost-waves might have worked on longer hair. The result here made us wonder if Knightley had cut her hair herself that morning.