My year old Border terrier bitch has recently vomited on two occasions while out for a walk. The first time she had been out for about 1.5 hours in the woods , mostly off the lead. She vomited twice on this occasion, once in the woods and once on the short car journey home.The second incident happened today, again while out. This time she'd only been out for approx 30 mins and had mostly been on the lead. Idon't know if all this is relevant info, but would really appreciate the advice.

Depends what she was sick, was it grass? if so I wouldn't worry, dogs do it all the time.
Dawn.

Dog do vomit if they have eaten grass and often in the mornings when there is too much bile in the stomach. If your dog is well and not off their food I would not worry, I have a bitch who will always vomit if she finds a piece of apple, because she swallows it whole.