Recent advances in micro- and nanotechnology have produced a number of new materials which exhibit exceptional potential for the design of novel sensing strategies and to enhance the analytical performance of biosensing systems. The interest in coupling these two aspects, nanomaterials and biosensors, derived from the consideration that most biological systems and molecular interactions belong to the nanometre scale. This book, therefore, shows three interesting types of miniaturisation pathways for electrochemical biosensing applications: the employment of carbon nanotube thin films, the combination of a microfluidic system coupled to magnetic particles and the construction of polyaniline nanotube arrays. These sensor devices generally resulted in better sensitivity, specificity and faster response compared to current solutions. This overview should highlight how research in the nanobiosensors field is rich and challenging and how the evolution of fabrication techniques will allow the realisation of smaller and smaller devices, able to provide the development of faster, more reliable and highly sensitive analytical systems.