That soulful gaze

A perfect example of the dichotomy between dog-to-dog versus dog-to-human facial expression is eye contact. Between dogs, eye contact signals aggression.  Between humans, eye contact is an integral part of communication. Humans reward eye contact from humans as well as dogs. 

Blinking or squinting during eye contact

If a dog blinks while making eye contact with you, he may be contemplating what you’re thinking.

Eyebrow-raising

When your dog raises one eyebrow or both while making eye contact, it’s a sign of alertness and interest, says Schoeff. Here’s an opportunity for you to engage with your pup, maybe teach him a new trick.

Yawning When Not Tired

If your dog is well-rested and still yawning, it’s a sure sign that your pup is stressed.

Smiling

This position usually indicates happiness, but it can also serve as a warning if your pup is really showing its teeth. When a smile becomes a snarl, it can be a warning to anyone or anything around that your dog is showing off its weapons.