I created a new user group. ACP > Members > Groups > Create a new Group
After i tried to make the new user group invisible for other user who are not member of the new user group.

Is this possible?

Unfortently that's not possible at the moment 

50 minutes ago, Daniel F said:

at the moment 

Is there something planned to do it?

I'd like this as well. At least have the ability to set a group as not searchable when searching for members.

We need this feature.

If this hasn't been built yet, I vote for this.

You're voting for this in the wrong section.  You need to make a post in Product Feedback.