If you're working with different kinds of clients, or maybe creating ads for your agency that you don't want your clients to see, you can limit who can view specific ad categories!
Here's How:
Go To:
My Categories
Select the "edit" button next to the category you'd like to work on
Make sure the category is "Enabled"
Under the "Clients" section, enter in the clients that you want to give access to
Hit Save
That's it! Super simple. Now only those clients listed in the clients section will see that category.
NOTE: If there are not clients listed in the category section and the category is "enabled", then every client will be able to see that category.