Typically, someone who is in agreement with you will smile and nod as you speak. (Disagreement shows up in compressed or pursed lips, clenched jaw muscles, or a head turned slightly away, so eye contact becomes sidelong.) But smiles are often used as a polite response and to cover up other emotions.

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You have one shot to make the best impression possible, because as you leave the room, someone else will brush past you and smile.

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Some pictures will always make you smile.

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Then you look at her and smile a smile your dissembling face will remember until the day you die.

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Even so, they know what any professional interrogators will tell you: A disarming smile, a few seemingly random questions, and a monitoring of body language are far more likely to detect terrorists than brusque treatment and formulaic questions.

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You will look more comfortable, conscientious and caring if you smile slightly EVEN when you are delivering bad news.

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Your smile, your pizzazz and whatever charm you have will come through more to the host and producer in-person.

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Folks who agree with you might smile, nod, or even vocally endorse your views, while others will quietly look for your professional alternative.

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