This book represents a collection of 30 selected papers from thework of John W. Cahn. Dr. Cahn is Senior Fellow at the MaterialsScience and Engineering Laboratory of the National Institute ofStandards and Technology, and is widely recognized as a founder ofmodern theory and thought in materials science. The range of hisresearch included kinetics and mechanisms of metallurgical phasechanges, surfaces, interfaces, defects, quasicrystals,thermodynamics, and other areas impacting the fundamentalunderstanding of materials science. Each paper includes a 2-4 page review of the impact andhistorical perspective of the work. This is an important collectionfor students, instructors, and scientists interested in materialsscience.