The deregulation of the telecommunication industry is providing the basis for a competitive, open market in telecommunications services. The TINA Consortium is developing a software architecture that aims to support both communication and information services in an open services market. This paper examines the suitability of TINA for use in an open services market based on Internet technology. An implementation of a composite, IP-based service that uses features of the TINA Service Architecture is presented, and the implications for the wider integration of TINA and the Internet in the delivery of open services are discussed.