My dog will raise her lips in a sneer whenever I do something she isn't comfortable with such as petting her while she is laying down, or hugging her when she isn't in the mood. She never growls and I don't know if she would bite because I back off before she gets to this point. I never hit her or yell at her when she does it, I just say NO and she'll stop usually. Or she'll just walk away if she feels bothered. Is this a response to something she doesn't like me doing - or is it a dominance thing? She doesn't exhibit any dominant tendencies in any other way. Is it better to stop what I'm doing and she'll stop - or should I do something more so she knows who's boss. If you yell at her she gets really scared, so it's not like she wants to be mean.

you should say no and walk away. you certainly not praise her or else she might do it more often. once you say no to her in a big firm voice, walk away from her and ignore her for a while. after doing this for a while, she might start to understand that showing her teeth is a bad thing to do.

Watch the show Dog Whisperer, he covers this over and over again. He is fantastic and you will learn allot.

im not sure if your dog is being like my dogs or if she doesnt like what you are doing. my dogs acually smile (lift their lips up) at us when we come to see them or when we come home. if your dog is like mine, she might just be smiling because she's happy you are hugging her. im not sure, but that could be the case. if she's not doing it to smile, maybe you are in her space too much. try hugging her but not as much. maybe pet her first, then hug her. like you said "she's doing it in a sneer" it might not be a sneer. i hope this helps.