Zeta Beta Zeta (ZBZ), also known as Zeta Beta or ZBZ is a top sorority at CRU based on academics, athletics and philantropy. It even has a national network, lead by a National Council of former ZBZs. Like the other Greeks on campus, there is a hierarchichy based on a pseudo-politic and on bounds of sisterhood (each active chose a pledge every year to became is big sister and help her to fit in ZBZ, they remain bounded for a long time after that).
- Rebecca Logan, active, president
- Ivy, active, standards chair and Ashleigh's "little sister"
- Betsy, active, former social chair
- Laura, active, former Penhellenic liaison
- Abby, her pledge class president
- Heather, Heath's sister and Rebecca's little sister
- Mandi, member of Rebecca's pledge class who helped make Casey miserable in season 1 and at the start of season 2
- Frannie Morgan, former president and creator of IKI, Casey's big sister
- Beth, defected to IKI
- Suzanne, former ZBZ Standards Chair
- Libby ,kicked out prior to 1.08
- Andrea, left in beginning of 1.12
- Jordan Reed, former pledge who dropped out of school before becoming an active
- Jen K, former pledge who wrote an article about the Greek System
- Casey Cartwright, pledge educator, rush chair, former Panhellenic liaison, former president, Rebecca's big sister, and former House mother
- Ashleigh Howard, former president, former social chair
- Teegan Walker, ZBZ Nationals representative and member of the Grand Council
- Kiki, Frannie Morgan's big sister and also Robin Wylie's pledge sister.
- Robin Wylie, Ashleigh Howard's big sister and a lesbian.
- Lizzi, Nationals rep
- Virginia Horton (mentioned in 1.06 "Friday Night Frights")
- Trudy Henderson (mentioned in 1.06 "Friday Night Frights")