Multiple Campaigns

Hello - Is there a way to verify and ensure I don't accidentally send people on multiple campaigns at the same time?

On the "upload contacts" screen. It is important that you always leave the checkbox NOT checked where it says: "Tag Existing Records" as seen here:

(Please read the charcoal colored comment box that is in the red circle in the photo)

This will prevent any duplicate records from being created in a new tag or group.

The next important thing to remember, is that you should only add ONE tag to ONE campaign.

Thanks - but there may be times where I would like to tag existing contacts into new campaigns when uploading. Is there a way to omit those folks when they are already part of another campaign. In other words, I may re-use contacts for new campaigns, but I don't want them to ever be on two at the same time. Is there a way to do that?