After a very successful conference in 2020, the IEEE International Conference on Blockchain and Cryptocurrency in 2021 (ICBC 2021) will be held in the oldest and biggest Australian city, Sydney. ICBC 2021 is the third installment of the IEEE Communications Society (ComSoc) sponsored conference on Blockchain and Cryptocurrency. It will feature keynotes, tutorials, peer-reviewed technical paper presentations, posters, demos, a hackathon, and exhibitions from world-leading service providers, solution vendors, research institutes, open-source projects, and academia. A select number of papers based on the peer review process will be invited to submit an extended version for publication in a Special Issue of the IEEE Transactions on Network and Service Management. ICBC 2021 is the primary forum for the technical exchange of the latest research and innovation, regulation, policies, standards, and applications in the exciting and emerging area of blockchain and cryptocurrency.