You can see who is on leave by using the Leave Calendar.
For users with a Member profile, this will show Approved Leave Applications for employees as well as any pending applications for themselves. They will not be able to see pending Leave Applications for other employees.
To see the Leave Calendar in ESS:
Go to Dashboard.
Select Directory.
Select the Leave tab, which shows all employees who have approved leave in the selected date range.
Note: If members do not see the Directory, you will need to manage the permissions for the relevant role under Settings, Roles and Permissions.