The author includes not only information about the most important advances in the field of cryptology of the past decade-such as the Data Encryption Standard (DES), public-key cryptology, and the RSA algorithm-but also the research results of the last three years: the Shamir, the Lagarias-Odlyzko, and the Brickell attacks on the Knapsack methods; the new Knapsack method using Galois fields by Chor and Rivest; and the recent analysis by Kaliski, Rivest, and Sherman of group-theoretic properties of the Data Encryption Standard (DES).