Introducing new potential friends

Hi, was hoping for some advice with socialising buster. He's a four year old boy who's been in kennels over the last few months. Unfortunately we don't have a great deal of history on him apart from his owner was sent to prison and he was left homeless! From what we were told he used to live with another dog and the shelter have said whilst with them he was good with other dogs. We are hoping that he can enjoy or at least tolerate being around other dogs but have had several mixed messages from him. When we first met him we walked around the kennels and he paid no attention at all to the dogs barking around him, on our first walk we came across two terriers off their lead and he was very polite with them,, sniffed gently to say hello them sat down at my feet and ignored them. We were very impressed and hopeful however since then we have bumped into a staff and boxer who he really did not like cue much growling barking etc especially with the staff as they actually went for each other (thankfully both dogs on lead and easily moved away) I'm now concerned how to introduce him to any dogs and wondering if to book some dog training classes with him. What's the best way to proceed. Any advice greatly appreciated. We are not letting him of lead at present unless in an enclosed area and no other dogs around tho he is good at recall and doesn't seem to go to far from us especially without checking we are following. Many thanks for any advice
Sal

Well in my time they get on with some and not others. Moo is pants on lead she tugs and is just not very nice, she also hates boxers full stop. Its just something we cope with and deal with. Off leash she is a gem but I can read her body language so very well. You need to know your dog and by the sounds of it I don't think classes will help, but always worth a go Xx

I did some classes and found them great for training but I don't think it would of helped with socialization, although all classes will not be the same. Perhaps you could speak to some potential trainers?

As Janey said if he's funny with some dogs will be best to learn to read his body language, have a look at this link

http://staffy-bull-terrier.com/dog_body_language

Thanks guys. Think we just need more time to get to know each other so I can read the signs that he's not happy. Today he's been great walked past another dog loose behind a tiny fence and didn't bat an eye lid and didn't show any signs of aggression when another dog came into the vets so maybe he's just choosy about who he likes (I can relate to that )

That's good. Its just progress and entertaining different circumstances x

Another good day today. Whilst out on our walk a small white terrier came round the corner ( think it had run out of a house as could hear people chatting round the corner) we stopped and they had a sniff of each other, no barking or growling from either of them. We then moved buster away. I was so nervous he would eat said small fluffy pooch so pleased he was nice, think I need to learn to relax a bit, my heart was in my mouth :/ have enquired about training classes only do one to one training to start with hopefully he'll catch on fast as £20 an hour will bankrupt me if he's a slow learner lol

That's great  Yes do try not to be nervous as he'll pick up on your anxiety!

If you get a good trainer that is breed aware it can only help matters , even if its just a case of teaching you some tricks to relax you a bit and handle him in the correct way , apart from that all you can do is look for the socialising opportunities and try to maximise on them but always proceed with caution and as above fact of the matter is many of our dogs like to pick and choose their friends ( both mine do )