If you're trying to get ahold of an administrator at one of the nation's prestigious theaters this weekend and you can't reach them, you might want to check Open Book in Minneapolis.

That's where representatives of nearly 40 companies will convene to learn about Ten Thousand Things' unique model, which brings TTT stagings of new and classic work to prisons, shelters and other non-traditional venues.

"So many theaters are now using or interested in our model that we decided we should all get together," said Michelle Hensley, who will retire as TTT artistic director at the end of this season. Participants in the sold-out conference include The Public Theater in New York, Old Globe in San Diego and Center Stage in Baltimore.

They'll be learning about which stories work best in unconventional settings, where it makes sense to take shows (along with where it doesn't) and how the TTT style -- in-the-round, with only basic props, sets and lighting -- is realized. (The next TTT show, "Park and Lake," premieres in February 2018.)