It depends on the dog's body language. So far I haven't met one that had body language that told me that I was in danger, so I usually bend down and offer my hand for a sniff and then check for a collar and tags.Our friends thought we were crazy because on vacation a couple of years ago there was a Rottweiler running loose through our campground. I was standing at the end of the trail that lead to the spot where we went to the bathroom waiting for my husband and heard some rustling in the woods to my left and when I looked over there was a 100lb Rottweiler running at me. I knelt down and held out my hand and she started licking my face. We were able to get her into our truck and took her to the vet on the island because the only tag she had was a rabies tag. He knew her (it is a small island in the middle of Lake Michigan...everyone knew everyone) and was able to contact her owners. They decided that they didn't want her any more because she kept getting out and had snapped at the husband when he was trimming her nails. We ended up convincing the vet to take her to a rescue in MI. When we left he was on the same boat with her in tow headed to the rescue. 
I am glad that we were able to help, because otherwise she would have been put down. We wanted to take her, but were in a pet free apartment at the time and had no where to keep her until we found a place she could live with us. She sure was a sweet beautiful dog!
I am glad that we were able to help, because otherwise she would have been put down. We wanted to take her, but were in a pet free apartment at the time and had no where to keep her until we found a place she could live with us. She sure was a sweet beautiful dog!