This paper describes a new direction of ISDN towards Broadband ISDN (B-ISDN) and a philosophy for applying ATM technology aimed at implementation in the B-ISDN, which is the primary telecommunications network currently evolving toward the 21st century. In addition, the most likely evolution scenario from existing networks towards the B-ISDN is presented from the view point of transport capability enhancements, according to a study on future service vision, VI&P.