By in large we play by most of the USCA 9 wicket rules with many of their optional rules as well (click here for details). After many years of play our sister club, the Keene Croquet & Hunt* Club and its founder Ken Arnold came to use some of their own adjusted rules. We play by these rules as well and believe them to be the best for challening 9 wicket croquet.
"Chess on grass" is what we play.
Incidentally about 90% of the rules we play by are the same as those published in 1874 in the old Brooklyn Daily Eagle. Click here to see the original article with the rules!
The Commissioner (Gabe) shall have the final ruling in any disputes that may arise during play. When in doubt, ask The Commish.