There are many enterprise architecture (EA) metamodels. Although there has been some attempt to produce a single, definitive metamodel (e.g., TOGAF or ArchiMate), and although EA repository and tool vendors produce detailed metamodels (e.g., Troux or Mega), the topic remains contentious. Is it possible to have a single, all-encompassing metamodel to which everyone can subscribe? How do EA teams reconcile differences between their various metamodels? And how do EA metamodels relate to metamodels in other disciplines, such as ITIL or COBIT? This Executive Report explains why it is impossible to have a single EA model and highlights the techniques currently used to allow for the rationalization of the metamodel maze and improve EA communication through better metamodeling techniques. The report also explains the vital link between the metamodels, views, and viewpoints.