The laugh attack is coming to Boulder.
Pearl Street Mall will be one of nearly 30 spots around the world that will participated in World Laughter Day.
Betsy Janowak, organizer of the event, says the day will be a time for people to get together and laugh for no reason.
Organizers say World Laughter Day is a nine-year-old tradition that began in India.
But it isn't all fun and games.
Janowak says laughter can sharpen your mind, boost your immune system and aid digestion.