Telecommunications networks of the future will exploit two new network architecture concepts that are currently being implemented, or soon will be. These are the Intelligent Network and ISDN, the Integrated Services Digital Network, which together will support a full range of voice, data, and image services that Information Age telecommunications users will demand. These new network architectures, operating synergistically with intelligence in terminal systems, will constitute a framework in which users and service providers will link together standardized functional components to create customized services. These components, along with interfaces and signaling protocols at the interfaces and within the network will result from continuing national and international standardization efforts. In the planning of these new architectures, a few major goals are of paramount importance: • the achievement of a flexible network structure in which functionality is distributed among the network components in a way which supports the timely and economic introduction of new services in response to user needs; • the establishment of industry standards at the interfaces between network elements such that service suppliers can choose among a set of available systems products in building their networks and avoid dependence on a small set of suppliers, • the development of standard user interfaces supporting signaling procedures which can provide the user with increased control of, and access to, services to satisfy his needs; Achievement of these goals will result in the realization of an Open Network Architecture. The ISDN and Intelligent Network architecture concepts are described in this paper.