This Recommendation | International Standard provides: a) a model for reasoning about, representing, managing, and developing re-usable specifications for relationships between resources; b) notational tools for specifying relationships, their representation, and management; c) definitions of generic management information that may be used in the representation and management of relationships; d) guidelines for the development of conformance statement proforma; e) example definitions. The general relationship model is specified in clause 7. The notation tools are specified in Annex A. The generic management information is defined in clause 8 and Annex B. The guidelines for the specification of implementation conformance statement proforma are given in Annexes C and D. An illustration of the representation methods and example definitions are presented in Annex E and Annex F respectively. A commentary on the text is included in Annex G. This Recommendation | International Standard does not provide a mechanism for the maintenance of consistency between resources that is implied by a relationship. CCITT Rec. X.732 | ISO/IEC 10164-3 specifies a model of relationships represented by attributes and a set of generic attributes for representing specific types of relationships. The modelling concepts and specification tools defined in this Recommendation | International Standard are applicable to the definition of relationships in general, and hence, are also applicable to relationships represented by attributes as modelled in CCITT Rec. X.732 | ISO/IEC 10164-3.