Multifunctional electronic textiles (e-textiles) or wearable electronics, capable of detecting changes in environmental conditions, monitoring human body functions, and local computation, have enormous potential in everyday and defense applications. One of the major challenges in realizing this potential is to have conformable and effective fiber-based sensors and energy harvesters. My Master's Thesis project seeks to improve the piezoelectric responses of breathable PVDF-based membrane for sensing and energy harvesting, and incorporate the membranes in smart shoes. Specifically, the project explores how the performance of piezoelectric PVDF-based membrane can be improved by adding organosilicate nanoparticles, controlling fiber orientation and the conditions of the electrospining process, and how to embed the membrane sensors in the shoes and interface it with a computer and/or smart phone to monitor foot pressure and body activities. iii