They have been condemned as a secret society, their rituals are ridiculed and their members get accused of cronyism.
But what is Freemasonry really all about? Who joins the Freemasons and why?
BBC Inside Out reporter Tony Roe was invited to film behind closed doors and what he discovered may deflate a few of those conspiracy theories.
He visited the maze of corridors and rooms that makes up Leicester's Freemasons building on London Road, which houses the biggest collection of Masonic memorabilia outside London.