The phenomenon of hair pulling has been recognized for centuries, yet the true prevalence of trichotillomania (TTM) is largely unknown and the topic has been sparsely studied. TTM is classified as an impulse-control disorder despite much debate about its etiology. In this review we summarize the different hypotheses, including impulse-control disorders, obsessive-compulsive disorders, behavioral problems and addiction, and the appropriate treatment methods. The combination of selective serotonin reuptake inhibitors and antipsychotic medications are shown to be most effective. Treatment with anti-addiction drugs seems relevant. Further research is needed to increase our knowledge regarding the etiology of TTM.