Advances in sensor technology and in digital positioner and variable speed drive algorithms, combined with smart features, offer a step change in the performance of modern measurement instruments and final elements. The installed accuracy of many smart instruments has increased by an order of magnitude. There has been a correspondingly dramatic reduction in the drift of transmitters and a similar improvement in the resolution of control valves. This comprehensive resource aims to increase awareness of the opportunities afforded by modern measurement instruments and final elements, and to show how to get maximum benefit from the revolution in smart technologies. It builds an understanding of the fundamental aspects of measurements, measurement instruments, and final elements for applications in the process industry. The terminology and ideas presented provide a firm foundation for subsequent chapters that focus on what is needed for lowest life-cycle cost and best automation system performance. The last chapter provides a comprehensive exploration of the technology that supports the rapidly expanding opportunities of WirelessHART instrumentation. No prior plant experience with industrial process instrumentation is required. For students and new employees, the chapters on fundamentals will improve productivity on the job and form a basis for further study. For the seasoned veteran, the book offers insights and serves as a guide through today's myriad automation products and application details. It provides a picture of the state of the art for 95 per cent of the field instrumentation and final elements used, or under consideration, in a modern process plant. The reader is encouraged to seek further information on particular types of measurement instruments and final elements, which is available from manufacturers via the Internet and in instrumentation handbooks and ISA publications.