Permission is an important feature in Sharepoint, however, it cannot be applied to item or column. With sharepoint Permission, users can set item or column permission easily. Its main function lies in:

1. Assign permissions to all items separated from list permission settings. There are times when you need to control permissions to all items but not want to inherit permissions from parent list permission settings. SharePoint Permission Boost Workflow can solve this problem instead of manually setting permissions to each item. With it, permission settings will be automatically applied to each item when this item is created or modified;
2. Assign ITEM-RELATED users or groups permissions to each item. For instance, in a task list, you want the assignee of one task, but not some specified users or groups, to have read permission to this task. Since each task item has its own assignee, it will be  difficult if you set read permission to each item when assignee is appointed or changed. SharePoint Permission Boost Workflow brings in a concept named “ITEM-RELATED users or groups”, which actually means user or group columns in a list, to solve this problem. Configured in the workflow association page, user or group columns, which represent “ITEM-RELATED users or groups”, are assigned permissions to all items. The workflow is running in background; when item is created or modified, the “ITEM-RELATED” users or groups will be assigned permissions to the item.
3. Assign users or groups read/edit permissions to list columns. SharePoint does not define column permissions by default, but SharePoint Permission Boost controls column permissions by overwriting some control templates.

Find further information on

http://www.sharepointboost.com/permissionboost.html

And feel free to contact: services@sharepointboost.com

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