We live in a time when people jump from skyscrapers with specialized parachutes on their backs, climb hundreds of meters high vertical rock faces without any safety gear, perform loops in a hang glider at six thousand meters, ride waves from the height of multi-story buildings on a surfboard, jump over 40-meter high cliffs on skis or snowboards, and plunge down massive waterfalls in kayaks. The athletes who engage in these sports operate in a boundary of the possible, where even small mistakes can lead to death. Why? What drives these individuals to willingly put their lives at risk? Are extreme sports an escape from an overly civilized life, where there is otherwise nothing left to experience? Is it the thrill of danger, obsession, euphoria, curiosity, or even addiction that draws people to these limits?.