The main reason for buying PDF Pro 10 initially was to enable me to combine a number of separate PDFs into a singe master PDF. I have followed the help instructions and it just does not do what the instructions suggest. I first open my first file, then go to the Insert and Edit tab, select the Document Attachments Tab, then the + tab to identify the files I was to attach, then I selection the files I want to attach using the Open tab in the dialogue box and finally hit the Save tab. I provide a new file name for the combined files, and then all I get when it saves is a single file, the last one on my list. An added weakness of this feature is that it is not easy to interactively alter the order of the files to be combined into a single master, you have to plan this out when you add the files. Otherwise the other features seem very comprehensive, so if you can explain what I am doing wrong I am likely to be a happy customer. In the meantime the help instructions are just not adequate to attach the files successfully.