This book addresses new ways to optimize the fabrication process and performance of iron-based superconducting wires and tapes based on the powder-in-tube (PIT) method. Further, it systemically analyzes and enhances the current-carrying ability of wire and tape conductors with regard to chemical addition, mechanical deformation, and heat treatment. The microstructure of the superconducting cores is studied by means of the magneto-optical imaging technique, high-resolution transmission electron microscopy, and flux pinning analysis. This book will benefits all students, researchers, and technical personnel who work in superconducting materials, applied superconductivity, and the power industry.