Tibetan Mastiffs have such a strong presence, it’s often said that they’re nearly human. They’re giant dogs—some as big as 160 pounds—that aren’t very active. Instead, they’re solemn, gentle, and extremely watchful, making them good family guard dogs. Some owners say their Mastiffs will get upset if their human family gets angry with one another, even when they’re rough housing or wrestling. Many owners trust their Mastiff’s judgement of character so much that if their Mastiff doesn’t warm to a new person, they investigate why, since they’ve found there’s a pretty good chance that their Mastiff is right.