Japan's Ministry of Internal Affairs and Communications has commissioned 12 organisations -including the Toshiba Corporation, Mitsubishi Electrical Corporation, Tokio University, the National Institute of Advanced Industrial Technology -to start research and development of a global quantum cryptography communications network. Spanning 5 years (until 2024), the project envisions the development of a network that can accommodate over 100 quantum cryptographic devices and 10 000 users. It also explores four technological targets: (a) quantum communications link technology for high-speed, long-distance, and high-availability links in quantum cryptographic communication networks; (b) trusted node technology that ensures the robustness and tampers resistance of cryptographic key management systems, and improves the confidentiality, integrity, and availability of quantum cryptographic communications; (c) quantum relay technology that extends distances and secure cryptographic key relays on the ground; (d) wide-area network construction and operation technology, which manages and controls wide-area and large-scale quantum cryptographic communication networks.