As wearable microelectronics are becoming ubiquitous, there is a growing interest in replacing batteries with a means of harnessing power from the user's environment via embedded systems. Efforts have been made to prolong the harvester's operational lifetime, overcoming energy dissipation, lowering resonant frequency, attaining multi-resonant states, and widening the operating frequency bandwidth of the biomechanical energy harvesters. Such technological advances mean harvesting energy is a viable solution for sustainably powering wearable electronics for health and wellbeing applications, such as continuous medical health monitoring, remote sensing, and motion tracking. The book introduces the concepts of vibration-based piezoelectric, electromagnetic and hybrid energy harvesters, and addresses their modelling, fabrication and characterization. It covers the fundamental principles and details the most advanced functions, including biomechanical and space applications. Detailed descriptions and explanations of a wide range of related concepts are provided, such as multi-degrees of freedom hybrid piezo-electromagnetic insole energy harvesters, non-linear 3D printed electromagnetic vibration energy harvesters, and finite element analysis of hybrid piezoelectric and electromagnetic energy harvesting. Also included are trends towards design, modelling, fabrication, and characterization of nonlinear multimodal electromagnetic and hybrid piezo-electromagnetic insole energy harvesters, as well as describing and explaining electromagnetic and hybrid piezo-electromagnetic energy harvesting technologies. The book provides an extensive and up-dated survey of the published scientific and technical articles and conference reports, covering more than 340 references. The book concludes with an outlook from the authors on likely future developments and applications. Energy Harvesting for Wireless Sensing and Flexible Electronics through Hybrid Technologies provides in-depth coverage of the topic for researchers from academia and industry, as well as advanced students with an interest in the field.