As one in the series of classroom training handbooks, prepared by the U.S. space program, instructional material is presented in this volume concerning familiarization and orientation on magnetic particle testing. The subject is divided under the following headings: Introduction, Principles of Magnetic Particle Testing, Magnetic Particle Test Equipment, Mediums and Their Preparation, Magnetic Particle Applications, Classification of Discontinuities, and Comparison and Selection of Nondestructive Testing Processes. High product reliability and quality in metal processing are the main concerns through the volume. The material is designed for use in the classroom and practical exercise portions, and successful completion of the corresponding programmed instruction handbook is the prerequisite for receiving classroom training. Included are illustrations for explanation purposes and tables of magnetic characteristics. (CC)