Create Smart Mailboxes
Smart Mailboxes are mailboxes for which you define specific criteria, and which Mail fills with matching messages without moving them from their original location. Essentially, they’re saved searches you only need to set up once. Rules for inclusion can be time-based; you might make a Smart Mailbox for messages received in the last week, or for older, unattended inbox items.
The VIPs feature is helpful for identifying messages from important people. However, try combining “Sender is VIP” and “Message is unread” rules. That will give you a smart mailbox with messages you haven’t even looked at from senders you consider to be vital contacts. Smart Mailboxes, like regular ones, can be added to the Favorites bar for quick access – drag one from the sidebar onto it.