Greek life is a huge part of campus, and it seems to dominate the social scene. Greeks almost exclusively throw all on-campus parties. Students wearing Greek letters are a common sight, and fraternity/sorority exclusion becomes most obvious at Wismer during dinner—the frat guys and sorority sisters sit at certain tables every night. But it's not necessary to be Greek to fit in. While a third of the campus is a member of a Greek organization, one must remember that this is a small school. It'd be nearly impossible to avoid befriending someone who is not a Greek. Therefore, most parties are not exclusive, and non-Greeks can get into them quite easily. There are a few exclusive parties, but those are usually rare.
A few non-Greeks view frats and sororities as a stain on the Ursinus landscape, but generally, most students don't seem to mind. After all, a lot of the Greek organizations participate in campus life. A few are involved with community service; others provide services such as flowers for Valentine's Day or stress-busters during exams. Most Greek organizations actively try to have a positive influence on campus life, so non-Greeks usually tolerate their presence.