This book constitutes the refereed proceedings of the 1998 International Conference on the Theory and Application of Cryptographic Techniques, EUROCRYPT '98, held in Espoo, Finland, in May/June 1998. The book presents 44 revised full papers selected from a total of 161 submissions. The papers are organized in sections on distributed cryptography, complexity, cryptanalysis of block ciphers, computational algorithms, paradigms for symmetric systems, public key cryptosystems, multi-party computation, digital signatures, Boolean functions, combinatorial design and analysis, elliptic curve systems, and electronic commerce and payment.