The article sets out the nature, the history and the general structure of the crime of genocide and provides a comprehensive analytical commentary of the elements of the crime. Against the current trend of the international case law to expand the boundaries of the definition at the risk of the crime's trivialization this article develops a strict construction even if the results may appear politically unattractive. The article starts from the premise that, for all practical purposes, the occurrence of a crime of genocide entails a collective destructive act. This collective act forms the objective point of reference of the required intent to destroy a protected group in whole or in part; the vain hope of an individual to contribute, by way of commission of one of the underlying offences, to the destruction of a group falls short of this concept of a realistic genocidal intent. The article rejects a purely subjective definition of the various categories of protected groups and cautions against the conversion of the crime of genocide into an unspecific crime of massive human rights violations based on discriminatory motive. At the same time, it is submitted that not every campaign of so-called "ethnical cleansing" is to be considered as the infliction on the group of conditions of life calculated to bring about its physical destruction in whole or in part. Regarding the mental elements of the crime it is held that, contrary to a widespread belief, it is the interpretation of the terms "destroy" and above all "part" (of a group) that determines the general scope of the crime to a much greater extent than the construction of the word "intent". The predominant narrow interpretation of the word "destroy" in its physical and biological meaning is supported while it is noted that the most recent ICTY case law reveals an inclination of re-introducing the concept of social group destruction through the backdoor of the words "in part". The extension of those words to comparatively small regional communities is probably the most conspicuous aspect of the general trend to over-expand the crime's definition. Conversely, the reference to the particularly heinous character of genocide is not good enough an argument to accept the many flaws of the prevailing purpose-based approach to the word "intent". The article suggests instead that the word "intent" means that the perpetrator commits the prohibited act with the knowledge to further thereby a campaign targeting members of a protected group with the realistic goal of destroying that group in whole or in part.