This book will discuss advances in the area of functional thin films for sensors and novel concepts for future breakthroughs. The focus will be on guidelines and design rules for sensor systems, interaction between functional thin films and other sensor subsystems, fundamentals behind the intrinsic functionality in sensing thin films and nanostructures, state-of-the-art technologies used to develop sensors today and concrete examples of sensor designs. Coverage of nanoscale thin films for sensors includes the following important topics: Fundamental physics of functional thin films and nanostructures; Synthesis processes of functional thin films; Integration of functional thin films; Applications of functional thin films in sensing.