It can be useful to create a newsletter for the following use cases:
Reasons for this could be 
* a separate subscription and unsubscription procedure 
* a separate report is required 
* different test delivery lists 
* separate billing  
In this case, you can set up different customers and different departments of your company, for example, as clients under Account > Client Management via the button Create new client.
Reasons could be 
* a separate report is required 
* different test delivery lists 
* separate billing  
In this case, select your customer as the client in a campaign.
You can find detailed instructions on creating clients in the article “Why do I need clients?”
Under Addresses → Lists → Newsletter, you can create a new newsletter by clicking the button at the bottom right. A corresponding auto target group is automatically created for each newsletter. 
 
Name your newsletter and select a client. You can also enter a short name, a description, which is then displayed by default as the description text on the newsletter administration page, and a customer code.
You can also check the boxes for activation and visibility.
When creating newsletters in omnichannel clients, you can define a daily automatic cleanup of addresses without channel opt-in.
If the newsletter is assigned to a channel, the associated auto target group is automatically cleansed of all addresses that do not have an opt-in in this channel. If All channels is selected, no automatic cleansing takes place.
The assignment to a channel is only available for clients that use multiple communication channels (e.g., email, app push, SMS, WhatsApp, print, web-push, or voice).
 
To assign existing auto target groups of a newsletter to a channel, please contact promio.net support.