This SharePoint 2010 designer workflow explains, how we can give item level permission to list items using SharePoint designer workflow in SharePoint 2010.
In SharePoint 2010 you can give item level permission to list items by the Manager Permission link, But this is suitable for fewer items and it will be very difficult to give permission to each item if your list is very big.
But there is a very good approach by using a SharePoint 2010 designer workflow. You can visit the below article that explained in details step by step. This is really really a very useful post by Adam Burden, which also explained with proper screenshots.
Hope this SharePoint 2010 tutorial helps to Change Item Level Permission using SharePoint designer workflow.
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