El-Sayed has made broad fundamental contributions to many research areas in the field of electronic and molecular dynamics. His pioneering experiments have yielded deeper understanding of the mechanisms of electronic dynamics in many systems of different length scales ranging from gaseous molecules; ions; gaseous clusters; molecules in condensed phase; amorphous and crystalline solids; nanoparticles and photo biological systems. The Ahmed Zewail Prize was presented during the 2009 Spring meeting of the American Chemical Society, in Salt Lake City, USA. About the Ahmed Zewail Prize in Molecular Sciences The Ahmed Zewail Prize in Molecular Sciences is awarded on a biennial basis to an individual scientist who has made significant and creative contributions, particularly those of a fundamental nature, to any of the disciplines of molecular sciences. The awardee's research activities may cover theoretical and/or experimental aspects of studies in all phases of matter and biological systems. The Prize consists of a monetary award of US$ 20,000, a Gold Medal, and a certificate. The awarding of the Prize takes place at the Ahmed Zewail Prize Award Symposium at the ACS Spring National Meetings.