These are the refereed proceedings of the International Conference on the Theory and Application of Cryptographic Techniques, EUROCRYPT '99, held in Prague, Czech Republic in May 1999. The 32 revised full papers presented were selected during a competitive reviewing process. The book is divided in topical sections on cryptanalysis, hash functions, foundations, public key cryptosystems, watermarking and fingerprinting, elliptic curves, new schemes, block ciphers, distributed cryptography, tools from related areas, and broadcast and multicast.