Exclusive ride time (ERT) is a period of time set aside by an amusement park to allow exclusive access to one or more attractions. Sessions are usually scheduled outside of a park's normal operating hours, or the attractions may be closed off to the public during the ERT period. Exclusive ride time is often reserved for private corporate events, celebrity functions, season passholders, special ticketed events, members of the media, or enthusiast groups such American Coaster Enthusiasts.