On the Campaigns “Setup” page, you can set the campaign to only go to either those Subscribers who DID open a previous campaign, OR those who DID NOT.
You can also set “Actions” to be taken with the records of selected Subscribers.
1. COPY or MOVE a Subscriber record to another List if they Open the email they receive on this Campaign.
2. COPY or MOVE a Subscriber record to another List when the Campaign is Sent.