Hi

I am using SharePoint 2010.

I have a SharePoint site with 10 calendars on it.  The users want each of the calendars to have the same functionality i.e. Everyone has permission to add to the calendar, but once an item has been added the item's permission needs to change so that only the creator and an admin group have access to update/delete (Contribute) to the item.

I can easily create a workflow using the Set Item permissions - but this means creating 10 workflows - one for each of the calendars, and if it is ever changed I will need to make the changes in 10 places.  (I also believe once news of this functionality spreads other Sites in the same Site Collection will want to use it.)

I have thought of creating a User Defined Action so I can pass the List Name and the Admin Permission group as parameters.  My first problem was that Set Item permissions is not available in UDAs - so I thought of using a web-service call,  I have tried to find which web-service to call - I think it is Lists.asmx rather than Permissions.asmx - Is that correct ?  If it is correct what would the batch look like ?  I haven't been able to find any examples of updating permissions.

I have also thought of creating a Site workflow which is called each time an item is created.

What is the most efficient way to achieve updating item permissions in the same way for multiple lists ?

Thank you for your advice

Catharine