Boundry Problems

Hey Y'all,
I have a problem that I'd like some advice on.
I live on a 40 acre farm.  I have a 2 year old Hound dog mix.  My problem is that 6 months ago she started to chase us down the road when we would leave and go to our neighbors house.  She's still doing it...[:@]She only use to go to our neighbors house when we would leave now she goes over when ever she feels like it.  When ever she's here I always try to give her lots of attention.  I always feed her when shes here.  Anyway, I'm also concerned that she will get hit by a car or worse that someone will get hurt trying not to hit her.
If you have any suggestions I would greatly appricate it.
Thanks so much,
Anna