Halliburton Energy Services is pleased to contribute this important technical volume on Nuclear Magnetic Resonance Logging to the petroleum industry. The NMR logging represents a new revolution in formation evaluation with wireline logging, and this book gives a comprehensive treatment of this new technology. Since its acquisition of NUMAR in 1997, Halliburton has focused on advancing NMR techniques, and on integrating conventional log data with the NMR interpretation methodology to further enhance the NMR applications. To this end, a new NMR tool has been introduced, new data processing techniques have been developed, and new data interpretation packages (such as our real-time NMR answer product) have been made available to the industry. Besides explaining basic NMR principles and applications, this book provides an understanding of these latest achievements in NMR logging.