Since time immemorial, men experiment with increasing the size of their penis. Inserted foreign bodies in the penis have been known for long in several cultures. In some subcultures the habit of self-harm of the penis for augmentation is widespread today, as well. The book describes the various lay and medical activities that change the size of the penis to enhance sexual pleasure. The Vaseline has been being used for penile augmentation or thickening for more than 100 years. The method of Vaseline self-injection for penile thickening is especially prevalent among prisoners. We carried out a survey in Hungary's six largest prisons on penis augmentation by Vaseline. Almost two thousand convicts filled out the questionnaire. 15.7% of the respondents admitted that they injected Vaseline into their penis. The patients commit self-injection of Vaseline to emphasize their masculinity, but often instead of the intended result, complications occur and the treatment is surgical. The book presents the results of 78 patients undergoing surgery for damage suffered as a result of Vaseline self-injection.