Soil water measurement methods encounter particular problems related to the physics of each method. For TDR, these relate to wave form shape changes caused by soil, soil water, and TDR probe properties. Methods of wave form interpretation that overcome these problems are discussed and specific computer algorithms are presented. Neutron scattering is well understood, but calibration methods remain critical to accuracy and precision, and are discussed with recommendations for field calibration and use. Capacitance probes tend to exhibit very small radii of influence and thus are sensitive to small scale changes in soil properties, and are difficult or impossible to field calibrate. Field comparisons of neutron and capacitance probes are presented