Metamaterials-by-Design: Theory, Technologies, and Vision is devoted to a comprehensive review of the latest advancements and current trends in the field of system-level-oriented metamaterial design methods, technologies, and future perspectives. Starting from the theoretical and methodological motivations of this research and covering macro-scale performance-driven design of volumetric and planar metamaterials, the book introduces advanced task-oriented modeling approaches. The approaches discussed include specific reference to their multi-scale / multi-physics customization in recent metamaterial science and engineering. In the introduction of these concepts there is particular attention paid to the illustration of the physical mechanisms and phenomena at the basis of the field manipulation capabilities enabled by metamaterials. Then, a wide set of recent application examples in microwave, terahertz, photonics, and optics scenarios is reviewed, highlighting the logical and methodological interconnections among the different domains. For example, contributions from industry and academic perspectives on active and passive metamaterial-enhanced devices for communications and sensing are included. The final part of the volume is aimed at providing a perspective regarding the current trends, future research, and application tracks in system-performance-driven metamaterial design methodologies and technologies, included potential applications in future reconfigurable and cognitive materials. Metamaterials-by-Design is suitable for researchers and engineers in academia and R&D in industry working in materials science, engineering, and related applications areas.