In recent years there has been a remarkable convergence of interest in programming languages based on Algol 60. Researchers interested in the theory of procedural and object-oriented languages discovered that Algol 60 shows how to add procedures and object classes to simple imperative languages in a general and clean way.Volume 1 contains an Introduction, historical and foundational material, and works on language design; all of this material should be accessible to beginning graduate students in programming languages and theoretical computer science.