Please ignore the fact that I am writing dialog junk that already exists. There's more to it than that. Each anchor element has an HREF attribute with a URL to an image. If I comment out the line where I modify the source of the image I create in the click handler (Line #7), the popup DIV shows up exactly right. However, leaving that line of code in, it forces the browser to navigate to the image src URL and I have no idea why.