My RB collies, Cody and Willie, were very people-friendly dogs. I even took them into nursing homes as part of a pet therapy program before, but both of them had one incident where they 'went ballistic.'

Cody's incident was when he was really still pretty young, around a year or so old. I was fishing off my grandma's boat dock on the lake, in a private cove area, when a man came cruising in on a boat. He slowly edged the boat up to the dock, and was staring at me the whole time. Cody went crazy suddenly, snarling and barking for all he was worth, and I could not calm him down, nor did I really want to. The man suddenly gunned the motor to his boat and sped off. That was the only time in Cody's 12 years that he ever showed aggression.

Willie's was when he was around 5 I believe. I used to take the dogs out for nighttime walks in the summer, because it was so hot during the day in southern Missouri. Well one night a man was coming from the other way, and Willie went berserk, lunging and snarling and barking at the top of his lungs. The guy hastily walked by, keeping to the other side of the road. Willie never again showed aggression either.

Tasha barks/growls at all new people who come around the house, especially men. She did one time take a lunge at someone walking by me on a walk, totally shocked me and seemed to come from no where. Several people had walked by her and she had even let some kids pet her without batting an eyebrow. I was walking her down the sidewalk and a lady with a stroller came from the other way. I held Tasha close, was afraid the stroller might freak her out, but she totally ignored it. But then another lady came walking up, she was alone, and Tasha suddenly snapped and lunged at her. She's never done that before or since... I really was shocked, and still have no idea what was wrong. I have always kept a closer eye on her around men, because she is much more distrustful of them, but she's always been really good with women, often coming right up to greet them when she sees them.

Tommy loves people though is very shy with new people. He wants to come see them but will stand just out of reach wagging like crazy for awhile. One night my husband came home late after being out with his brothers doing something. He was dropped off by one of them, so he didn't drive and the garage door didn't open, he just came in the door. Tommy freaked and did a pretty impressive growling/barking episode until he realized it was just Daddy. David praised him for 'protecting Mommy' hehe.