I had been painting all day; exhausted and went outside with my 15 month old male GSD ..... he has been 100% on recall ... notice the has been. We were sitting under the tree and I tossed the ball at the same time my neighbor was walking her dog past the yard. Well he went for the ball then takes off towards the dog who is in the middle of the street and ignores me. Thank goodness he is not dog aggressive but the poor girl who was walking her dog.
Well I know its back to the basics but wanted your opinions and feel I need my butt kicked too. Please feel free.
I have read again all the articles on this site regarding the recall but want your opinions on how best to make sure this never happens again. Since he is 15 months what do I have to look forward to in the next year as he matures?
My reaction at the time was to walk up to him, apologize to the poor girl and corrected him back to where he should have stopped, literally kicking his butt.
Tell me what you would do from here on out.

I would NEVER intentionally have my dogs loose outside of a fenced area. Except long line work for recall practice in a park or something like that. I'm not a great, experienced trainer and don't trust my dogs to be 100% reliable off of a training field. I've got thousands of dollars in time and cash invested in my dogs. I don't want them hit by a car or mauled by another aggressive piece of shit that some old lady (who has her dog on leash) can't control.
Another thing, your dog is still probably young in the head for 100% reliability. I probably wouldn't correct him to hard for failing a proofing session, just go back to the point of failure and deliberately work with more distractions. Off leash in public is risky business. I would never do it. But then again, I live in a heavily populated area where danger for dogs is everywhere. The only dogs that live freely and happily are the strays that nobody cares about.

Another thought. An E-collar would be a great alternative to a leash in public. This way you can give the dog a little reminder when he flakes.

Sometimes I take my dog to a park for some off leash retrieving. When I do this, I put a check cord on him. I made my own out of a length of poly rope and a swivel clip that I bought at the hardware store for less than $5. If I see something that I am concerned might be too tempting for him, I can easily step on the cord and redirect his attention to me. He has never bolted on me under these conditions. I find that the check cord extends my area of influence. If I call him and he hesitates or tries to blow me off, I can give a quick pop on his prong from a distance, but I find that I rarely have to do that.

IMHO, distractions should be proofed in a secure area. After 100% proofing(LETS HOPE)then move into the introducing the dog to different stimuli that will be a distraction in unsecureed area.
All these new distractions should be done on leash or long line. This should not be rushed for any reasons. Add distractions slowly, continue to proof using different stimuli that you will encounter in normal everyday activities.

Remember during the distraction traing sessions always go back to one that was proofed, this will end the session with both you and your dog leaving the field satisified.

Proofing off leash should be another question when you get to that point!

This sounded like something that would happen to me with my dog. I wrote recently about him chasing a skater. I guess it is better to keep using the long line and be safe. What gets me is that on one of the busiest steets in Brooklyn a guy with a flower stand has a male pitbull 6yrs old that stays outside his store all day as hundreds of people pass by. There is a high school down the block and a bus stop on the corner. I asked the guy how did he train the dog. He said he has just been doing this since he was a pup. He also walks around the corner where there is a small lot to relieve himself.I saw this with my own eyes and was envious. Jerry

Despite this is an old post, I find here exactly the problem I have today. Thanks for all your answers before I even asked.
I still need some more advise.
My dog is a Giant Schnauzer of about 17 months old. About basic obedience, we have already gone successfully through a rather high distraction level. The dog always minds when we are alone, or walking in the street (I keep him leashed in the street), or by bicycle, or with other working dogs around. Bycicles, cars, kids playing football, even growling dogs, are no longer a problem when we go out together. He was also able to get the BH all right. We still have a real problem with playing dogs. We forgot about the long line several weeks ago, as I began trusting my dog, and today he did it again: in the park, he ran after a female (which was not in her period) to play and just didn't bother to come back. He got corrected for not coming. But I got really concerned, because the first time breaking may be more difficult than the next times...
I intend to put the long line again, go deliberately go into any group of dogs in the park, let him play, then call him from time to time; maybe a sit command, anything, then release. Until I never have to correct him. Is it OK or should I try something easier before, and what? Now we do only about 5-10 min of training each day, and I randomly ask him to perform a command during walks.
BTW, I forgot to mention that our trainer told me there is nothing that can be done with this particular dog, concerning the bad habit of running away to play whenever he feels like it. I refused to believe the trainer in this matter.