Hi everyone I'm new here and hoping some of you can help/advise with issues I'm having with my dog... I apologise in advance for the long post. She's a 12 month old collie cross - we're not sure what she's crossed with, just that her mum is a collie... they thought labrador when she was a pup but definitely not so sure now. In the last couple of months she has started to get aggressive with new dogs. She will either run up to them or allow them to come to her, have a sniff and then snarl/growl/snap at their face/neck area and she has pinned some dogs down before, especially the smaller ones. It used to be now and again but now it's almost every dog we meet - apart from a couple of the regular dogs that she knows, she doesn't attack them, just ignores them. I thought it used to be possessiveness over a ball or stick or whatever she had at the time, but she seems to be doing it even when she's not playing with anything now. If any dogs come up to her when she's on the lead, she's really bad. More recently she has started getting aggressive with humans. She's fine with me and my partner at home, but if any strangers come to the house, she barks non stop at them and will snarl and snap if they try to fuss her. The same thing happens when we're out and about if strangers try to say hello to her. We have been to puppy classses and socialisation, she's very good at tricks and things like that. She used to be good at recall but now that has gone completely out of the window so I don't feel I can even let her off the lead any more which is a shame because, as a young collie, she has a lot of energy. She pulls on the lead too sometimes which we can't seem to stop, we've been trying to train this for months and nothing's working. Even our regular friends who dog walk/sit for us occasionally don't want to do it any more in case something happens. If you have read this far... thank you. I just don't know what to do!