Have I told you how wonderful Hyaflex has been for my elder cat (now 15 years old)? About 3-4 years ago I noticed she was no longer jumping up on the sofa but would stroke against my ankles for me to pick her up. So I thought well, she's getting old, and I proceeded to make it easier for her to get up and down on furniture and window sills (steps to climb up and down, pillows to jump down onto, etc.). Then a few days before Thanksgiving 2 years ago, her left hind leg started to give out when she tried to walk and she would just lay down until she was ready to make another effort. Frightened, I took her to the vet and x-rays showed bony growth on the hip vertebrae (picture a dog bone-shaped cookie cutter with the rounded bumps on either end becoming pointed). The vet said that there was nothing to do for her, not even surgery. Most likely she had hurt herself by falling, and she was slowly improving. A friend recommended Glucosamine & Chondroitin. I checked the small pet section at a local health food store and found they did not carry G & C for cats but they did have Hyaflex. I had read about Hyaluronic Acid and how research was showing it appeared to have the ability to help the cartilage between joints. So I bought the Hyaflex and within a month I could tell Lucy was feeling better. She has gotten better ever since, and over time has resumed adding the occasional fast trot to her sedate pace. In this past month (after being given Hyaflex for 1 year 8 months), she is making higher jumps than I have seen her do in years (high enough to jump on the sofa if the seat cushion were removed) and one morning she even ran down the hall for a short distance. I keep telling myself I have got to start taking Hyaluronic Acid supplements!