This book is aimed at the practicing engineer who is involvedwith the design, fabrication of operation of zirconium corecomponents. The Metals Properties Council, as part of itscontinuing role of collecting, analyzing, and updating materialsproperties data, has arranged for the preparation of this book. STP815 presents the reader with pertinent metallurgical andphenomenological aspects of creep in zirconium and zirconium alloysand the different ways in which this information is used in thedesign of core components for nuclear reactors.