I'm working on a portion of my site that allows people to search through a series of articles. I want to sort the articles by category. The problem is, most articles can be placed into more than one category. For example, if I write an article: "Rock Climbing Techniques to Prevent Injury and Increase Strength" I would want this article to be coded under: Rock Climbing Injury Prevention Strength Training While I could manually place the article in each of it's categories, I'm sure there is a simple way to use PHP and MySQL to assign multiple categories to each article and then have these articles pulled if someone clicks on the appropriate category or searches for the right keyword. If anyone knows of a good website, book, free code or script source etc that they could point me to that would be tremendously helpful. Thanks! Peter