Milly is a fantastic dog to walk with as she gets such enjoyment from her walks, sniffing out squirrels, finding the odd tennis ball left by someone else or old discarded plastic bottle, tracking deer/rabbits/etc and its great when there's only her and me and occasionally someone else in the distance.
BUT she really doesn't like other dogs sniffing her backside and can get quite snappy with them if they try - same if they sniff near her face when she's got a ball or some other 'irreplaceable item' in her mouth.
So if there are several dogs around I have to be very watchful with her/them. I can spot the signs 99% of the time, and can usually pre-empt any issues with her.
I wonder if she's like this though because I've usually taken her out in the very early or very late hours of the day when there are generally fewer dogs around so she's not been overly socialised. Don't know really, but we've learned to live with it. Aside from that, she's my very own stress reliever, whether its walking or just sat with her staring adoringly at me (probably trying to psych me into giving her a biscuit really ... but I can fool myself can't I??) or her giving my feet a good old licking.