Natural gas is rapidly becoming the fuel of choice for everything from home heating to power generation. The determination of the water vapor content in natural gas is one of several key factors in determining the ultimate quality of the gas. With economic conditions as they exist today, many companies have been forced to cut personnel in order to maintain a reasonable balance sheet. The loss of experienced measurement technicians places a heavy burden on instrument manufacturers to provide an accurate and reliable means of determining the water vapor content of natural gas. This paper will review the different sensor technologies in use today and also address key issues and proper procedures in assembling a sampling system to provide a clean, representative gas sample to the sensing device