Wagging Tail Happy Dog?

Just because a dog's tail is wagging does not necessarially mean they are happy. You need to look further at your dog, ear position, head position, overall body posture. Usually if your dog's tail and entire body is wagging then they are happy. If the tail is stiffly wagging, head is erect, along with slower more deliberate body movement, means a higher degree of tension. If you observe that dog; then you probably don't want to approach.