I think glucosamine is wonderful. I started taking 1500 mg. per day in February of 2001, after I heard about a study on the Today show that showed its effectiveness in dealing with osteoarthritis. People who took nothing lost cartilage, while people who took the glucosamine either did not lose anymore cartilage or actually gained some. I have terrible knees and just about gave up doing anything with impact or doing any strength training for the lower body that involved lunges. Now, after taking glucosamine for almost a year, I am jumping and doing all the impact on Cathe's videos with almost no modifications, doing SH legs with a 45 pound barbell, MIS lower body with a 35 lb. barbell, and PS Legs with 40 lbs. I really cannot recommend glucosamine too highly. Just make sure you take 1500 mg. I had to wait more than 3 wks. before I really noticed a difference, but my knees were really bad.