The 10th International Conference on Implementation and Application of - tomata (CIAA 2005)washeld in the Technopole of Sophia Antipolis, France, on June 27-29, 2005. This volume of the Lecture Notes in Computer Science series contains the notes of the two invited lectures, the 26 papers selected for presentation at the conference, and the abstracts of the eight posters that were displayed. The papers and posters were selected amongst 87 submitted papers. The submissions came from countries in ?ve continents. They show applications of automata in many ?elds, including mathematics, linguistics, networks, XML processing,biologyand music. The elderly lady of automata is aliveand kicking, ready to face the new challenges of computer science. Based on the reviews, the Best Paper Award was given to Markus Lohrey and Sebastian Maneth for their excellent article on Tree Automata and XPath on Compressed Trees (see page 225). This award was generously sponsored by the University of California at Santa Barbara. We wish to thank all the Program Committee members and the additional referees for their e?orts in refereeing and selecting papers, and maintaining the high standard of CIAA conferences. We are grateful to all the contributors to the conference, in particular to the invited speakers, for making CIAA 2005 a scienti?c success. ‘ We also thank the Computer Science Department of the EcolePolytechnique Universitaire of the University of Nice - Sophia Antipolis for accommodating CIAA in its buildings and providing the logistical support.