The Italian Conference on Theoretical Computer Science (ICTCS '98) is the annual conference of the Italian Chapter of the European Association for Theoretical Computer Science. The Conference aims at enabling computer scientists, especially young researchers to enter the community and to exchange theoretical ideas and results, as well as theoretical based practical experiences and tools in computer science.This volume contains 32 papers selected out of 50 submissions. The main topics include computability, automata, formal languages, term rewriting, analysis and design of algorithms,...