In order to improve the deliverability of your emails and to prospect respecting the GPDR (cf. Understand GPDR), you can add an unsubscribe link in your sequences. If any of your contacts clicks on this link, it is automatically unsubscribed from your sequence and is added to your blacklist, which prevents you from contacting it.
To add this link
Go to your Sequences (1) and click on one of them (2) :
Go to the Parameters (3), enable the option "Include an unsubscribe link at the end of each email" (4) and click on Save the sequence (5) :
Et voilà! The unsubscribe link will be included as the following sentence in each email of your sequence:
"Do not receive emails from + your company name"
If your contacts click on the unsubscribe link, they are automatically unsubscribed of the current sequence and cannot be added to other sequences anymore. They are added to your blacklist. Also, they take the following sequence state in the sequence : Unsubscribed.