The symposium "Languages: From Formal to Natural," celebrating the 65th birthday of Nissim Francez, was held on May 24-25, 2009 at the Technion, Haifa. The symposium consisted of two parts, a veri?cation day and a language day, and covered all areas of Nissim's past and present research interests, areas which he has inspiringly in?uenced and to which he has contributed so much. This volume comprises severalpapers presentedat the symposium, as wellas additional articles that were contributed by Nissim's friends and colleagues who were unable to attend the event. We thank the authors for their contributions. Wearealsogratefultothereviewersfor their dedicated and timely work. Nissim Francez was born on January 19, 1944. In 1962 he started his mat- matical education at the Hebrew University. He received a BSc in Mathematics in 1965, and, after four years of military service, started his MSc studies in Computer Science at the Weizmann Institute of Science under the supervision of Amir Pnueli. After completing the MSc program in 1971, Nissim continued his studies toward a PhD, again, at the Weizmann Institute of Science and, again, under the supervisionof Amir Pnueli. Nissim wasawardeda PhDin Computer Science in 1976.