This paper presents the foundation upon which the contemporary knowledge of body integrity dysphoria (BID) is built. According to the World Health Organisation’s International Classification of Diseases, 11th edition (ICD-11), the main feature of BID is an intense and persistent desire to become physically disabled in a significant way. Three putative aetiologies that are considered to explain the insurgence of the condition are discussed: neurological, psychological and postmodern theories. The concept of bodily representation within the medical context is highlighted, with the concept of dysphoria, which was brought to the fore with the introduction of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), and the ICD-11. Contemporary issues of “justice” are addressed to identify ethically relevant distinctions between BID and sex reassignment surgery. It is argued that there is no ethically relevant difference between the BID actor’s desire for invasive surgical intervention and the wish of gender dysphoric individuals to undergo sex reassignment surgery procedures. Some BID actors self-mutilate, and this presents medical professionals with difficult choices regarding whether or not to intervene in order to satisfy the BID patient’s desire. Both abstention and intervention may lead to severe ethical complications for doctors and patients despite the positive outcomes in terms of quality of life for BID individuals who manage to undergo such procedures.