Hello

The intention is that you'd normally keep emails as a historic record of your communications with a contact; use assignment and status to manage a list of emails you need to process.

One approach is to add a custom field - maybe call it 'processed' - and use its value to determine whether a reply is required or not. You can use reports and views to show the set of emails requiring response; such views/reports can be shared with your colleagues so you all get to see a consistent view

Sorry for the late response.

Does this help?

James.