After you have opened a new or existing screen in the Screen editor, right-clicked an empty part of that screen and chose Properties in the pop-up menu, the Screen object properties window opens. On the Access tab in that window, you determine the access rights for this screen to restrict access to it, dependent on the user (login name in Windows) and its assigned role.

Click here for information on how to edit screen object properties in general.
On the current tab you'll find the following settings:

Access (Role, Access rights)

Here you may define which Roles have which Access rights to this screen. You can indicate for each role whether no access (None), Read access, Write access or Full access must apply. No access means the screen won't be visible at all; Read access allows the user to view data on the screen but not to edit it; Write and Full access allow the user to edit the data on this screen.

None and Read have priority over the deselected Read-only option for a screen, meaning that the deselected Read-only option only makes a screen editable in principle, but that you can still exclude certain users from doing that, through access rights. These two types of access rights also have priority over less limiting access rights set on other levels in the application or databases.
If a role is not linked to this screen, then each user linked to that role has full access by default, unless restricted by other limiting access rights. A user without a role always has full access.

Users are assigned to roles, in the application setup.

Note that setting access rights on screen level is rarely put to use, since there are better ways to prevent certain data from being edited or viewed, for instance by using application identification roles, or setting access rights on database field level (see the reference below for more information).

See also

Security in Axiell Collections