I have a 7 yr old GSD who is absolutely wonderful to look at, however she is hare footed. I bought her at 16 months of age. I had never heard of this condition before and was wondering what cuased it - I have b een told by several people different stories, firstly it is genetic, secondly it is caused by too much running on hard ground when young, too much running on soft ground!!  Kizzy is fine but very occasionally her front legs slightly give way if she is running fast as she hasnt a lot of spring in her step! Also her nails grow incredibly long very quickly because of the shape of her feet. (Long toes and slightly splayed when standing)Anyone have any answers??

Hare foot is desirable in a few breeds (Tibetan Spaniels being one) but the vast majority require a rounded 'cat foot'. Good feet are born, not made, but the correct care and exercise can have some effect on them. Keeping the nails short will help Clipping, filng or dremelling once a week), as will walking on hard surfaces.

I'm a little confused about your description of a lack of spring in her step - I'd associate that with incorrect slack pasterns, not hare feet.

I'd agree with Jeangenie, it does sound like the problem is not hare feet. Hare feet are a desired trait in many breeds. Hare foot describes the shape of the foot, and the toes should not be splayed as that is a fault.
You say the toes of the foot as splayed, this is not correct for hare footed dogs, splayed toes on a foot are usually seen because the dog is flatfooted.
I would therefore think your dog has weak pasterns and is flatfooted, from your description. I have been told, but am not sure how true this is, that some breeds can have problems because the tendons in the toes are not tight enough to keep the toes from becoming dislocated. I did see this in a GSD cross I had staying with me some years ago. He would run around ok then suddenly stop and his foot would look like he had suddenly gone flatfooted on one side of his paw, turned out he had dislocating toes.

I must admit she does look flat footed, but it is only what people have told me when looking at her feet.  The reason I was concerned is that I have a 12 wk old puppy and if it was caused by any of the things I had been told (apart from being born with them) I wanted to take extra care.

Why not have a chat with your vet? He/she should be able to put your mind at rest. What do your pups feet look like now?

Some people do mistakenly called a splayed or flatfoot a hare foot. To see a proper hare foot other than on a hare, have a look at a borzoi foot, (not Collugh though as Reg has always gone for the rounder cat foot).

One of my gundogs had an accident, and cut all the tendons in her leg, she went flatfooted on that one leg, luckily for me Colin Price was able to rejoin the tendons and her foot went back to normal.

my pup has perfectly rounded feet, but to be honest I have never seen feet quite like Kizzy`s!  As I have said they dont seem to really bother her apart from the occasional trip up! I do believe she might have weak pasterns because her legs go in a bit at the front rather then straight.  Only her front legs by the way, the back feet are perfectly normal.

Often much more noticeable on the front feet. Your puppy sounds as though he is very different, so I suspect that with the right kind of exercise he will be fine. A friend of mine always used to advocate exercise on hard ground, she told me that when they are old enough, to walk from one lamp post to the next then jog to the next then walk to the next and so on. She maintained this tightened the feet up and keep them good.