I'm not sure what you mean by "xxx fraternities".. does that just represent their various Greek letters?
As far as Panhellenic Association goes, it sounds like an organization reserved for your campus. Are all/most/some of the GLO's on your campus local chapters? If so, this might be the governing body for them, or at least the sororities. I know that at my school, the local sororities had what they called a "Panhellenic Council" (But it wasn't THE Panhellenic Council) to keep them all on the same track, kind of.
There is also THE Panhellenic Council and National Panehellenic Council (NPC). These are bodies that govern all national sororities: One of them governs traditionally African-American Sororities and the other traditionally white sororities, but I always mix them up
(I *think* NPC is for African-American sororities, but i could be wrong.)
(There are fraternity councils for fraternities, and a Professional Fraternity Association (PFA) for professional frats/sororities). For example, my fraternity is a member of PFA, so we share resources, ideas, etc. w/ other PFA members, and the PFA establishes guidelines (voted on by members/alumni of the GLO's) for the members. Whether it be GPA requirements or rush regulations or whatever.
Anyways, these bodies create and enforce general guidelines, i.e. Rush regulations, alcohol issues, membership requirements/limitations, etc.
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I will leave the more detailed (and definately more accurate) definition up to Barbara, as she is very knowledgeable in this area. Hopefully I've given you some idea of their purpose in the meantime.
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Phi Beta Fraternity for the Creative and Performing Arts.
http://homepages.go.com/~phibetaphichapter/index.html
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