The International Consultative Committee for Telephone and Telegraph (CCITT) program of work that addresses global international intelligent network (IN) standards and a framework for the standardized evolution of IN are described. Bell Communication Research's (Bellcore's) IN work, referred to as the Advanced Intelligent Network (AIN), is also discussed in relation to the CCITT IN Recommendations. In addition, IN activities of the European Telecommunications Standards Institute (ETSI) and the Telecommunications Technology Committee (TTC) of Japan are described.