This book presents throroughly revised full versions of the 21 papers accepted for the Fourth International Workshop on Conditional and Typed Rewriting Systems, CTRS-94, held in conjunction with ICALP '94 in Jerusalem, Israel, in July 1994. The volume reports the research advances in the area of rewriting in general achieved since the predecessor workshop held in July 1992. Among the topics addressed are conditional term rewriting, typed systems, higher-order rewriting, graph rewriting, combinator-based languages, and constrained rewriting.