I just recently discovered background layers in Visio (yes I’m ashamed it took so long and may refrain from calling me a Visio power user for a couple of weeks). Anyhow, if you don’t know about them yourself, create a new page in a visio document, right-click on the page and go to “Page Setup”. Simply set the page to “Background” and then go the page you want to have as a foreground. Again “Page Setup” and select the Background page you just created. Voila.
But I just ran into something annoying in Visio 2010 (may actually also happen in versions before 2010, but I just noticed in 2010). If you copy a complete page (=pressing Ctrl-C while nothing on the page is selected) and you have a background layer, Visio gets confused and messes up the copied image. It crops the image, makes it smaller somehow or whatever - but it’s definetely messed up. Continue for a quick-fix.
Steps to reproduce the issue
1. Create a background (set the page to “Background” in Right-click > Page Setup > Type).



Fixing it
1. Create a large canvas (ideally filled with white and a white line - here in yellow just for demonstration purposes) on the background page which spans the complete page.


This is not as bad a fix as it seems, because the large yellow canvas is not selectable (like anything on the background) in the foreground pages.