in Saarbrücken, Germany. This Festschriftshowsclearlyhowthe ?eld ofalgorithmicshas developedand matured in the decades since Kurt wrote his book with the same title. The classic approach based on discrete mathematics and computability and complexity theory continues to be the foundation of the ?eld with ever new and important challenges as the ?rst chapters of this Festschrift show. Kurt has contributed signi?cantly to classical algorithmics and gained worldwide repu- tion. Starting from research in computability theory in his PhD thesis he made major contributions to complexity theory, graph algorithms, data structures, and was one of the ?rst to recognize the signi?cance of computational geometry contributing one of the early textbooks on the subject.