The Big ONE 2008, a free two-day event focusing on community building and sustainability, takes place today and Sunday at Golden Gate Park in San Francisco.

The event will feature a Village of Engagement near the Children’s Playground in Golden Gate Park, where nonprofits, agencies and individuals from around the Bay Area will gather in theme tents.

Scheduled participants include city official Daniel Homsey, who will speak today at 10 a.m., Cafe Gratitude owners Matthew and Terces Englehart, and Maya Donelson of Graze the Roof, who will discuss the construction of a rooftop garden at Glide Memorial Church in the Tenderloin.