Creator
Chris Claremont, Paul Smith
  
Chris Claremont, John Byrne
  
Base
The Xavier Institute, Salem Center, Westchester County, New York State, (former) The Alley (beneath Manhattans surface), X-Factor Is sentient starship
  
(current) Emma Frost operates from the Massachusetts Academy, Snow Valley, Massachusetts, (former) Hellfire Club mansion in New York City, a home in the Berkshire Mountains in Massachusetts (near the Massachusetts Academy), and places of residence in vari