GSM and UMTS Acceptance in the World Section 1: Global Acceptance of GSM Friedhelm Hillebrand 1 22.1.1 Introduction Nobody amongst the early key players expected that GSM would become a global success. There was even deep concern whether it would become a success in all Western European countries. The GSM MoU signed in September 1987 2 differentiated between commitments for CEPT countries and the rest of the world: