Start from this link:

What are the privacy options for groups? | Facebook Help Center ...
https://www.facebook.com/help/220336891328465
There are 3 privacy options for groups: Public, Closed and Secret.
‎How do I add new members to ... - ‎How do I change the privacy ... - ‎Facebook

Someone has to go into their own FB account and use the tab in the menu options "group." Then you can create a group and put the privacy setting to "secret" which only allows members to see who is in the group and the posts that are made. The person that creates the group needs email addresses or the real names of people to invite them into the group. That is how it works. What that means though is there would be no anonymity for the members within the secret group (only from outsiders).

That's probly not wise from a security standpoint. A password kind of thing would be better. Maybe. Well, nevermind.

I don't have a problem setting one up, if nobody else wants to. I am on Facebook regularly. I don't mind other people who use TSM knowing my name, etc., I just would rather not share that information with people who are not using TSM. I am Facebook friends with co-workers and others in my profession, etc. I'd rather keep my problem drinking to myself.

This sounds wonderful. I'm actually in a number of secret FB groups haha
But I'm a bit paranoid I'll get found out... I know a lot of alcoholics (former bartender), so I always looking over my shoulder a bit, even on here!
On the other hand, fake profiles are exceedingly easy to create. Maybe I'll make one and give myself some absurd name!

I'm in. I'll be the one wearing fake mustache. How do we join. I nominate Msilaine our fearless leader and personal favorite.

Steve
(kinda excited to see all my new friends)

I would probably not join a secret FB group because even though the general public would not be able to see the posts, if someone got onto my FB page they can see the list of secret FB groups to which I belong. My Facebook page is always signed into and my daughter often grabs my computer to show me something on FB or my husband is looking over my shoulder as I watch some funny video a friend has posted. Maybe there is a way to hide the list and I am just not FB savvy enough to do it.

Ok...guess I'll try this. Secret facebook group named "inmates". Appears you must give me your facebook name so I can put you on the list. I think best give me your forum name too. If I don't kow you you won't be allowed. Can PM me. If this is rediculous pain in butt I,m gonna cancel. Or glad to make someone else admin. I will gladly take any advice.
Steve.

So...when I tried to add a member and start the group, a pink sign pops up saying "add friends to group". Does that mean I have to friend everybody before I can add them? And if so, won't all MY friends be able to see them? I am on another group and to join, I had to friend one member (assume moderator). ??
Steve.

I'm kind of like forget it at this point. Don't send me your stuff till I get smarter (not REAL likely).
Steve.