IPSJ Director

IACR World Cryptography Real World Crypto Steering Committee

IACR Test-of-Time Award 2022 Selection Commitee Member

IEEE Transactions on Dependable and Secure Computing Associate Editor

AsiaCCS 2022 The 17th ACM ASIA Conference on Computer and Communications Security Program Co-chair

IACR Real World Crypto RWC 2022 Program Commitee Member

CANS2025 24th International Conference on Cryptology and Network Security Programme Committee

The Casper Bowden Award for Outstanding Research in Privacy Enhancing Technologies 2021 PET Award Commitee Member

IACR Public Key Cryptography Steering Committee (2018-2020)

ACM Advances in Financial Technologies - AFT 2020 Program Committee Member

JSIAM 26th President

IEICE Vice Chair (2017-2018)

ACNS 2021 “Applied Cryptography and Network Security” Program Co-chair

ESORICS 2019 “European Symposium on Information and Computer Security” Program Co-Chair

IACR PKC2019 “Public Key Cryptography” Program Co-Chair

FC2018 “Financial Cryptography and Data Security” Program Co-Chair

FC2013 “Financial Cryptography and Data Security” General Chair

CT-RSA 2016 “RSA Conference Cryptographer's Track” Program Chair

IACR Asiacrypt 2012 Program Co-Chair

IACR Asiacrypt 2013 Program Co-Chair

MyData Japan Vice Chair

Sovrin Foundation Trustee (-June 2020)

Science Council of Japan Member (2014-2026)

JST Presto Advisor (IoT)

JST Presto Advisor (Math)

Ministry of Economy, Trade and Industry “Pilot Project for Building Digital Public Goods Using Web 3.0 & Blockchain Application” Special Adviser in the Pilot project（June 2024-）

Digital Agency “Expert Panel on Governance in Leveraging Verifiable Credentials (VC/VDC)” Committee member（March 2025-）