Internet addiction, sex addiction, shopping addiction, Facebook addiction – the list of new addictions could go on indefinitely. By the time we reach work addiction or marathon addiction, it becomes clear that in recent years we have been dealing with an almost addiction-like expansion of the concept of addiction. A critical assessment is therefore necessary. Which behaviors actually exhibit addictive characteristics? What should be recognized as behavioral addiction alongside established dependencies on psychoactive substances such as alcohol, nicotine, and other drugs? Where can individuals no longer manage vital risks and personal suffering on their own? Who needs to be treated professionally and with what prospects? This book addresses the fundamentals, diagnostics, therapy, and prevention of so-called behavioral addictions and their related areas.