Aggression Training Tips?

[catia]

I have a 3½ year old Boxer who seems to be aggressive towards men and other dogs.
My mother bought him when he was a pup from a local breeder and condo rules in her building prevented her from keeping him so a family friend took him in. He has always been familiar with us. Well now certain circumstances are preventing the friend from keeping him so now I have him and plan on keeping him the remainder of his life (i tried to get him the first time, my mom thought his needs were better suited with the family friend).
Im NOT positive on how he was trained and socialized the past three years the family friend has had him. Hes got basic commands and hes a very good dog, the aggression concerns me.
I have had other dogs in the past but they have been friendly with everyone, also my own training, so Im not quite sure where to start.
First thing that comes to mind is slowly teaching him to trust the men hes supposed to by introducing him but he barks and barks and barks until attention is diverted, which is not easy and long after the person causing aggression is no longer in site, he also tries to jump for the person and bite. I have thought about getting a muzzle to deter the biting while meeting trusted people until he knows not to but im really unsure about what kind of muzzle i should be getting for him, (again have never had to use these) because of the short snout.
Any and all tips and advice will be greatly appreciated!

 

[Gunther]

People aggression, yeah I got this. First if he's barking he's not likely to bite but it means he's not comfortable so he might!

I dealt with a GSD 100+lbs, and no barking! A low growl and a cold hard stare... that is a dog that will strike if given the chance! I never gave him the chance!

Go to the Leerburgh site or Google "who pets my puppy?" It can be fixed if he is a basically sound dog, he can learn what normal people to people interaction looks like but "not" by cramming people into his face! It takes time, patience and training,

And look up "why dog parks are a bad idea' while you are at it," you don't need to create addition problems for your self!

Ask questions here and I'll be happy to relay my experiences. But bottom line my dogie is now people and kid safe in public!

Note my dog is kid friendly even though he was not raised with kids but even my people happy Boxer(Struddell) was never allowed to be alone with kids! My policy. I don't have kids so my dogs are never unsupervised around kids.

 

[TwoDogs]

I have had other dogs in the past but they have been friendly with everyone, also my own training, so Im not quite sure where to start.

You could make this worse rather than better, especially if you don't know what you're doing. Find a good trainer that is experienced in behavior modification of fear-aggression using positive not punitive methods.

 

[Kisaq]

I second the notion of getting in a certified behaviorist or trainer who will work with you using positive methods. To help the dog figure out how great it is to know how TO behave and make good choices, rather than showing him how much bad stuff will happen if he does something the way you do NOT want him to behave.

"Aggression" shows in so many forms. Some "fixable" and some ... "manageable" ... and some ... well... not so much. And what you are seeing may not be really aggression at all...

But every case needs to be handled according to what's going on. And only an experienced professional will be able to evaluate the "reason" and "extent" of his aggressive responses.

On the plus side - it doesn't really matter to the dog (at this point) to you or to your training methods what may or may not have happened with this dog in the past. You need to deal with what's happening now and move forward with/from that.

Thank you for taking him on when no one else seems to be able to... but please be careful. You have a serious liability there and a big responsibility.

I wish you all the best.