This book constitutes the thoroughly refereed post-proceedings of the 5th International Workshop on Finite-State Methods in Natural Language Processing, FSMNLP 2005, held in Helsinki, Finland in September 2005.

The 24 revised full papers and 7 revised poster papers presented together with 2 invited contributions and the abstracts of 6 software demos were selected from 50 submissions and have gone through two rounds of reviewing and improvement. The papers address various topics in morphology, optimality theory, some special FSM families, weighted FSM algorithms, FSM representations, exploration, ordered structures, and surface parsing.