Kishigami Toshiaki was born in 1926 and graduated from Kyushu University in 1948. He joined Electrical Testing Laboratory of Ministry of Post and Telecommunication, a part of which was separated and transferred to the Nippon Telegraph and Telephone Public Corporation (NTT) as the Electrical Communication Laboratory in 1949. He joined the new laboratory and was engaged in the research of telegraph code transmission and the adoption of transistors to the telegraph transmission equipment. He was really a pioneer of digital transmission research in Japan.

From 1960 he launched and implemented the development of a computer called CM-100. which was to be used for the toll charge calculation and was the first transistor computer developed by NTT. CM-100 introduced the dynamic transistor logic, the advanced control for fetching instructions and data, the concurrent execution of multiple I/O operations and the macro instructions for acceleration. The most salient feature of the project was that he decided to use the logic simulator to manage and verify the logical design CM-100. This is the first in the world to adopt the computer simulation to design a commercial computer. The technologies developed in the CM-100 development laid out the foundation of the electronic exchange and data communication systems deployed by NTT later.

In 1964 he joined the DEX development project with his CM-100 colleagues, which aimed at the development of stored program controlled telephone exchange systems at NTT. He led the system design of the exchanges and proved that the information technologies were indispensable for the electronic exchange development.

DEX-1 was the first stored program controlled exchange developed in Japan.. For its development he enhanced the simulation technologies for CM-100 to the more modern CAD technologies in such a way to include automatic drawing of logic and wiring diagrams, automatic generation of placement and layout. These CAD technologies were transferred to the Japanese industry and widely adopted.

After the development of DEX he participated in the DIPS(NTT's on line computers) project of NTT and promoted the introduction of DIPS computers into the NTT business. In 1974 he led the development of DIPS-11 computers which incorporated the VLSI memories developed in the joint research project on VLSI between NTT and the Japanese LSI vendors.
In 1976 he moved to Nippon Electric Corporation and served as the President of NEC Software Inc. from 1981.

In 1983 he moved to Ibaragi University to educate the younger generation.
He was very much enthusiastic in the standardization of information technologies and served as the member of the Standardization Committee of IPSJ from 1967 to 1980. He succeeded the substantial hike of the membership dues of the committee and contributed to lay out its financial foundation.

He died on June 26, 2011.