Piezometers are instruments that with the right installation and monitoring procedures can produce high quality information. Attention shall be paid when prescribing the type of piezometer and the installation procedure in order to minimize errors and op-timize the quality of the information that can be obtained. The use of piezometers as geotechnical instruments is standard and, apparently, the installation procedure is easy enough so not so much attention is paid to it. The aim of the paper is to shown, by using several examples, how the use of piezome-ters can be optimized and the most standard mistake that should be avoided.