The papers contained in this volume were presented at the 18th Annual S- posium on Combinatorial Pattern Matching (CPM 2007) held at the University of Western Ontario, in London, Ontario, Canada from July 9 to 11, 2007. All the papers presented at the conference are original research contri- tions on computational pattern matching and analysis, data compression and compressed text processing, su?x arrays and trees, and computational biology. They were selected from 64 submissions. Each submission was reviewed by at least three reviewers. The committee decided to accept 32 papers. The p- gramme also included three invited talks by Tao Jiang from the University of California, Riverside, USA, S. Muthukrishnan from Rutgers University, USA, and Frances Yao from City University of Hong Kong, Hong Kong. Combinatorial Pattern Matching addresses issues of searching and matching stringsandmorecomplicatedpatternssuchastrees,regularexpressions,graphs, point sets, and arrays.The goal is to derive non-trivial combinatorial properties of such structures and to exploit these properties in order to either achieve superior performance for the corresponding computational problems or pinpoint conditions under which searches cannot be performed e?ciently.