This International Standard specifies the following: a. An abstract language for specifying, constructing, and managing technology neutral metamodels: A metamodel is in effect an abstract language for some kind of metadata. b. A framework for implementing repositories & integration frameworks (e.g., tool integration frameworks) that hold metadata (e.g., models) described by the metamodels and which uses standard technology mappings to transform MOF metamodels into metadata APIs. This International Standard also provides the following: a. A formal definition of the MOF meta-metamodel; that is, the abstract language for specifying MOF metamodels. b. A mapping from arbitrary MOF metamodels to CORBA IDL that produces IDL interfaces for managing any kind of metadata. c. A set of "reflective" CORBA IDL interfaces for managing metadata independent of the metamodel. d. A set of CORBA IDL interfaces for representing and managing MOF metamodels. e. An XMI format for MOF metamodel interchange (OMG XMI Specification).