Serial killers and sexual deviants aren't the only people who take pleasure in other people's pain. Sadistic personality traits are more common than you'd think — more than half of people show these ...

Internet "trolls" — people who intentionally incite discord in online communities — may have a lot in common with real-life sadists, new research suggests. In two studies conducted online, researchers ...

The following is an excerpt from my 2005 book Vulture: Profiling Sadistic Serial Killers. Believe it or not, we all know sadists. Some of them are our bosses, our spouses, our parents, siblings, ...