The work presents for the first time, in a unified method, all the significant legislative changes concerning the individual and collective rights of LGBTQI+ individuals in Greece and in the European and international space, as they have developed over the past decades. Starting with the necessary introduction, as well as the presentation of terminology and new legislative terms and definitions introduced by the regulations for LGBTQI+ rights and freedoms, this book attempts to gather all the legal information currently applicable to the entire scope of various cases centered on sexual orientation, gender identity, expression, and characteristics of individuals and collectives in the modern world. Especially in the first decades of the 21st century, Greek legislative production has included rules concerning the protection of individuals from unfair discrimination in the fields of work, service provision, health, and education, has standardized hate and prejudice crimes, has organized new self-determination procedures, such as the legal recognition of gender identity, the conclusion of civil unions and marriages, as well as the recognition of parenthood for LGBTQI+ individuals and couples. This material is supplemented by decisions of national, European, and international bodies that have shaped rules across the full spectrum of the above issues, including the recognition of asylum and subsidiary international protection for LGBTQI+ refugees. In separate chapters of the book, regulations are included for freedom of expression and public assembly, for the protection of personal data, as well as for health and protection from "conversion practices" and unfair medical acts. This entire legal material is classified into the ten chapters of the present book, with which an attempt is made to theoretically process and extract specific conclusions and highlight general principles governing the law of LGBTQI+ rights and freedoms. It is a reference work prepared by a practicing lawyer, with the aim of including, among other things, unpublished court decisions of Greek courts in cases handled by the author himself, as well as other co-functionaries of Justice, during the decades through which the emergence of this new body of knowledge, which tends to acquire legal scientific autonomy, runs.