As someone who wore glasses for MANY years, I unforunately tell you that you can't snorkle with glasses. The mask won't fit properly with the arms of the glasses, allowing water inside the mask. You can try to snorkle with contacts, my DH does that and doesn't have a problem. If your DW is like me, and can't/won't wear contacts(I've since had LASIK), her only option is one of the custom made masks with her perscription.