Ability to group report pages to organize them by subject

When you have 20, 30, 50 pages in a Report, it is hard to navigate. But also, 8 of them respond to a "Customer" perspective, and 5 of them to "Product" perspective, and so on. I suggest you can group pages behind a main theme (main page), so 50 pages show up like -say- 6 and behind each of the 6 the author can put the pages he considers appropriate. To navigate, when you clic a "main" page (one of the 6), one can peek at the pages below that (the tabs) so the user can go directly to a specific page or stay on the one in the top. Kind of Onenote style.