While you’re editing a layout on a page layer, nobody else can edit the same layer, but:

•Other users can edit other layers of the same page; for example, if you’re editing one editorial layers, Ads dept. can import advertisement on Ads layer.

•Other users can add, move, delete or merge layers of the same page, except the one you’re editing, and unless you checked-out the list of layers.

•You can move some objects on another layer, to allow to other users to edit them.

•Other users can edit any article, even the one you’re linking right now to a page.

•Other users can edit page master.

•Other users can edit page metadata.

•Other users can edit edition where the page belongs.

While you’re editing content of an article element, nobody else can edit the same element, but:

•Other users can edit other elements of the same article, if not opened by you.

•Other users can edit the structure of article, if not checked-out by you.

•Other users can edit metadata of the article, if not in editing by you.

•Other users can change the format of article elements, even of the one you’re editing.

To protect page elements against editing, lock them. To protect article against editing, send it in the folder where only you can access.