The subject of research in this paper is RM-ODP, an ISO/ITU-T international standard. We investigate an important challenge that the standard faces, specifically the absence of a satisfactory formalization of its proposed conceptual framework. We report on the definition and implementation of a concrete resolution for this challenge: a single consistent formalization of the RM-ODP conceptual framework. Our solution formalizes denotational and Tarski’s declarative semantics for RM-ODP. The formalization is based on the Triune Continuum Paradigm—a fundamental, logically rigorous object-oriented modeling paradigm that can be adapted by different modeling frameworks as a semantic foundation for their conceptual structures. D 2005 Elsevier B.V. All rights reserved.