Liquid water in a snowpack has been recognized for some time as a quantifiable variable of hydrologic significance. It is also important in the interpretation of snowpack microwave remote sensing data. One effective method for measuring the liquid water content of snow is freezing calorimetry. This technique is presented from theory through application including formulations for calculating the percent of liquid water in the snowpack. Silicone oil has been used successfully as the freezing agent. Consistent results can be obtained with the method, even when using newly-trained operators. Liquid water content data can be obtained approximately every 15 minutes when using two calorimeters and three operators. The freezing calorimetric approach was found to be accurate in determining the liquid water content of the snow to within ± 1.0-2.0 percent by weight.