We are a diving club, part of the CMAS global diving association. We used to have three mailing lists at our provider, using mailman. However, the service was changed and now we have "send-only" mailing lists, which are of no use to us.
Our diving club has only about 150 members, so that's the maximum size any of our mailing lists would ever be.
This particular list "monitors" would be for the instructors to plan and discuss training sessions and dives.
We would also like to have two other lists (in separate requests): one for the administration and one for all members of the club.
You can check our out site at: