It helped Bear a lot. When we first got him he could barely get up, let along walk any distance, or play with the other dogs his back legs were so bad and he was only 5. It's not an immediate pain relief like rimadyl or some of the others, more of a maintenance. We noticed a difference gradually over a couple of months. He'll turn 9 in October, and though he'll never be able to just jump up like the rest of the dogs, he can now walk over 3 miles, runs and plays with the rest of our dogs, can climb stairs, and goes up and down our fairly steep backyard. Hunter doesn't really have a problem, I mainly started him on it since I was putting him in agility and I know that can be hard on the joints, I figured it couldn't hurt him and may prevent future problems.