Canada Thailand Miikka Poikselkä Antti Toskala Nokia Bell Labs Nokia Bell Labs Finland Finland Tommi Uitto Karri Ranta-aho Nokia Nokia Bell Labs Finland Finland Petri Vasenkari Nokia Bell Labs Rapeepat Ratasuk Finland Nokia Bell Labs United States of America Venkat Venkatesan Nokia Bell Labs United States of America Jussi Reunanen Nokia Weide Wu Thailand MediaTek Taiwan Juha Salmelin Nokia Weidong Yang Finland MediaTek Taiwan Foreword The last 20 years have witnessed an impressive evolution in global mobile communi- cations from voice-centric 1G/2G services to 3G data services starting in 2001 and 4G mobile broadband starting in 2010. In Japan, NTT DOCOMO launched the world's first mobile Internet service, "i-mode," in February 1999 on the PDC-Packet(2G) system, and the service spread widely in Japan in the 3G era. The smartphone was introduced on the 3G system, and its use has spread in the 4G era. The numbers of mobile subscribers and devices have increased rapidly, and data usage has exploded. Data speed has increased from 2.4 kkps in 1993 to 1.2 Gbps in 2019, which is a 000-fold increase in just a quar- ter of a century. I have been lucky to be part of this evolution in NTT DOCOMO and to have seen firsthand such great achievements and also the great challenges the indus- try has overcome to manage the fast changes. We are now witnessing the beginning of the next major step in the evolution: 5G. We believe that 5G is one of the main pillars for providing value and excitement to customers and opportunities for value co-creation with partners in the 2020s. 5G also brings a number of new challenges the industry must meet in order to fulfill all these promises. NTT DOCOMO has been one of the world's leading companies in developing advanced technologies and services for new-generation mobile communication systems including 5G. NTT DOCOMO launched pre-commercial 5G services in September 2019 and will launch fully commercial 5G services by Spring in 2020 for serving customers in Japan and for providing a great specta