Grinnell has never had any fraternities or sororities on campus. All social events are open to all students. There are a few academic or honors fraternities, but they are not primarily social. The social events are available to anyone on campus and organized by the All-Campus Events (ACE) organization. The Student Government Association (SGA) even funds alcohol for all campus events.
However, the theme housing setup is like a Greek system in a way. There are seven theme houses, five of which are language houses. The other two change every year. Groups must petition for a theme and show that their theme will promote and provide something for the campus.