The rapid growth of smart textiles, high performance low power multihop networks, efficient processing techniques for smart antennas and ultra wideband represents a stimulus to provide new applications for on-, in- and body-to-body wearable communications for healthcare applications. This book explores the use of such sensor devices, smart textiles and other wearable technologies, applied to smart sensing in healthcare, including sport activity and health monitoring, radio communication aspects, and especially, energy efficient solutions with energy harvesting and storage.