The Church of Scientology Mission Sonoma is located on the upper floor of a historic building just off the Plaza. It offers religious practices and counseling based on the ideas of Scientology founder L. Ron Hubbard. It is open three days a week regularly, on Tuesdays, Wednesdays and Thursdays. Throughout the week, the church offers Dianetics and a range of personal-improvement classes including personality testing, time-management, grammar and individual counseling. According to the church's Web site, Wednesday night seminars are open to residents free of charge.