This comprehensive textbook delves into the fundamental principles of designing and testing engineering materials. Authored by Prof. Dr. Najm Abdel Amir Saeed, it provides students and practicing engineers with a solid foundation in material selection, the characterization of mechanical and physical properties, and standard testing methodologies. The book covers essential topics such as stress-strain relationships, failure analysis, and non-destructive testing, making it an indispensable resource for those in civil, mechanical, and materials engineering. It effectively bridges theoretical knowledge with practical, real-world applications, preparing readers to tackle complex engineering challenges with confidence and expertise.