In order to provide representative measurements of precipitation (rainfall, snow and hail, drizzle, sleet and so on), measuring devices must be deployed in suitable locations or sites and the instruments themselves exposed to the weather conditions they are intended to measure in a standardised manner. This chapter sets out what those standardised conditions of site and exposure are for measurements of precipitation, following the guidelines laid down by the World Meteorological Organization in the so-called CIMO guide (Commission for Instruments and Methods of Observation). Both manual and automated (recording) raingauge measurements are covered in detail, including tipping bucket, ground flush or pit gauges and weighing gauges, together with methods to decrease losses due to wind. Snowfall measurement methods are also covered.