Book excerpt: This book constitutes revised selected papers from the 22nd International Conference on Information Security and Cryptology, ICISC 2019, held in Seoul, South Korea, in December 2019. The total of 18 papers presented in this volume were carefully reviewed and selected from 43 submissions. The papers were organized in topical sections named: public-key encryption and implementation; homomorphic encryption; secure multiparty computation; post-quantum cryptography; secret sharing and searchable encryption; storage security and information retrieval; and attacks and software security.