Does anyone know of a PDF creator that will do layers OTHER than Adobe?? Layers can be turned on and off in most readers. This allows variations or added details to be displayed for each page. Like displaying a topo map with a grid and/or rivers and/or roads and/or a legend (or none of the above). I'm using Inkscape (FREE !!!) which does SVG files in layers, and will create PDF's as an output format, Unfortunately, it (currently) compresses all the layers together when it creates the PDF. I think someone on the Inkscape team is addressing this but it could be a while.