There is a ‘common sense’ understanding of sex and gender as binary. This is reflected in most European countries’ civil status dispositions, which are based on the assumption that everyone is born either female or male and will later identify as a woman or a man. People who fall outside of this binary sex and gender system are rendered invisible and suffer from the medicalisation and pathologisation of their bodies and identities. This contribution examines rulings, passed by the German and Austrian Constitutional Courts, that have recognised the right to personal identity and respect of private life for people who do not fit within the female and male categories. In said rulings, the public interest in maintaining a binary sex and gender classification system, founded on the longstanding argument that the ‘Western’ legal and public orders are rooted in it, has not been considered sufficient, proportionate and adequate to justify the lacking compliance of the civil status law with fundamental and human rights standards. Nonetheless, the legislative implementation of the rulings, consisting of the introduction of a third option besides ‘male’ and ‘female’, did not bring about the replacement of a legal status model based on a ‘sex as gender’ approach with one based on self-defined gender identity. Further actions will thus be needed to ensure full protection of the individuals‘ right to self-determination regardless of their sex characteristics, in line with the emerging international trend.