Brandi Glanville vs. Kim & Kyle Richards
Ah, Brandi Glanville's Game Night introduction to the Real Housewives of Beverly Hills. "At least I don't do crystal meth in the bathroom all night long, bitch," she snapped at Kim Richards, while Kyle called Brandi a "slut pig" and so on.
Bethenny Frankel vs. Jill Zarin & Kelly Bensimon
Remember them? Gone but not forgotten, the Bethenny Frankel vs. Jill Zarin tension marked the glory hears of the RHONYC. Jill wasn't alone in picking this fight. Kelly Bensimon, too, suggested Bethenny wanted her dead at one point, among other highlights.
Tamra Barney vs. Lizzie Rovsek
The Real Housewives of Orange County stars have gotten insane mileage out of Lizzie's birthday and Tamra's alleged party snub, ripping each other on and off camera.
Aviva Drescher vs. Carole Radziwill
This one is alive and well. Aviva Drescher and Carole Radziwill have more bad blood over their dueling book deals than most people have had in their whole lives about everything and everyone combined.
The Giudices vs. The Gorgas
All hell broke loose - at a Christening, ironically - when Teresa Giudice and her brother got into it over a whole host of long-simmering issues. Soon enough, their cousins, parents and friends alike where also getting in on the chaos.
Kyle Richards vs. Kim Richards
There's sometimes a serious lack of sisterly love between the siblings, particularly when it comes to Kim Richards' substance abuse problems and/or Kyle's insecurity.
Vicki Gunvalson vs. Gretchen Rossi
Gretchen Rossi and Vicki Gunvalson were never close, but after Slade Smiley called her ugly, Vicki called Slade a deadbeat, and it was ON.
Tamra Barney vs. Jeana Keough
Jeana Keough stirried up drama with Tamra Barney after Tamra accused her of talking to the press about her ex-husband Simon and their relationship. Tamra threw a cease and desist letter in Jeana's face ... then threw wine in her face.
Tamra Barney vs. Vicki Gunvalson
Tamra and Vicki got into a HEATED feud after the former supposedly mouthed off to Vicki and boyfriend Brooks.
Joe Giudice vs. Joe Gorga
They have since laughed it off, as guys are more likely to do with such things, but RHONJ fans won't ever forget Joe Giudice and Joe Gorga throwing down in one of the franchise's most intense moments.
Sheree Whitfield vs. The Party Planner
When Sheree Whitfield's party planner failed to live up to her expectations, she tore him a new one ... and coined the infamous line, "Who Gon' Check Me, Boo?"
NeNe Leakes vs. Sheree Whitfield
NeNe and Sheree got into it over… we don't even remember, but NeNe informed us she is very rich, bitch, then snapped her fingers and cemented her place in Bravo history.
Sheree Whitfield vs. Kim Zolciak
Don't mess with Sheree Whitfield, even if you're Kim Zolciak. An argument between them soon escalated quickly on the street when Sheree grabbed Kim's wig.
Adriana De Moura vs. Joanna Krupa
On The Real Housewives of Miami, Adriana De Moura tried to walk away from an argument, and when Joanna Krupa followed, she got clocked in the face, making for the most attractive (if not the most notorious) cat fight in Bravo history.
Heather Dubrow vs. Shannon Beador
While not as explosive as Tamra's many fights with her adversaries, The Real Housewives of Orange County stars Heather Dubrow and Shannon Beador are great for simmering, never-ending tension and surprising bitterness.
A little tense, Apollo Nida? Phaedra Parks' husband lost his mind on the rest of the cast during one major Season 6 altercation.
Bethenny Frankel vs. Jill Zarin
This feud was a slow-builder, but boy was it potent and lasting. Former best friends Bethenny Frankel and Jill Zarin started fighting and complaining about every little thing on the RHONYC until they eventually just hated each other.
Brandi Glanville vs. Joyce Giraud
Brandi decided Joyce Giraud should be called Jacqueline, that she was "a big fat pig" and that Puerto Ricans can't swim, or something to that effect. It wasn't pretty.
Sonja Morgan & Ramona Singer vs. Sobriety
The biggest enemy of Sonja Morgan and Ramona Singer might be the bottle. And everyone else of course.
Prostitution Whore. Table Flipping. Enough Said.
FIGHT! FIGHT! FIGHT! Lisa Rinna and Kim Richards absolutely get into it in this clip from The Real Housewives of Beverly Hills.
The feud to end all feuds, a long-simmering beef between Kenya Moore and Porsha Williams just plain erupted on The Real Housewives of Atlanta Season 6 Reunion.