We have a resource calendar in Exchange 2013 and want to be able to hide the details of other users bookings in a resource calendar.

At the minute, when a user clicks on the scheduling assistant in outlook, that can see all the other users bookings.

We dont want them to see this, only that it is booked.

Can anyone help??

Seems it is not possible

Resource calendar is shared for everyone, Every users have to see the bookings, otherwise wise meeting time will conflict.

Change the permissions on the "Default" user. For a resource calendar, they are set to LimitedDetails, which lists additional information:

PS C:\> Get-MailboxFolderPermission room:\calendar

FolderName           User                 AccessRights
----------           ----                 ------------
Calendar             Default              {LimitedDetails}

You can change this via the Set-MailboxFolderPermission cmdlet:

Set-MailboxFolderPermission room:\calendar -User Default -AccessRights AvailabilityOnly