I sent the last person who asked a very detailed description, but I will give you the Reader's Digest version....

An RR (round-robin) is when a group of people get together to trade by mail. One person in the group will form the round-robin and announce it to the board. The RR can be on any subject, such as "$1 house chips", slot cards, etc. It can be a little more specific ("$1 house chips that are blue from casinos beginning with B or C") or less specific ("Non-Atlantic City slot cards). The owner of the RR decides this.

So a dozen or so people send their names/addresses to the owner who will "seed" the pot with some number of chips/cards/keys/ice machines... ok that's stretching it... and will send it out to the first person on the list (maybe 50 cards, or 40 chips for example). This person (#2 on the list) will receive it and take a few, give a few - there is no set number except that it should be equitable (this is where the CC>CC ethics rules may come in) - take 6 and then give 6 or 7 for example.

Then #2 sends it to #3, etc. After each mailing, a message goes to the board with the name of the round-robin and the USPS confirmation (tracking) number. It will eventually get back to the owner who has a supply of items different (hopefully) that the ones he sent out a week/month ago.

The only cost to the participants is the shipping charge to the next participant.

Watch for announcement of upcoming RR's and sign up when one interests you, they move fast.