Precipitation is one of the most important abiotic variables related to plant growth. Considering the spatial variability of precipitation in relation to the area of interest (Eddy covariance system footprint), a single point measurement would satisfy the requirement as ancillary variable in ICOS. This measurement includes all precipitation in liquid and solid form: rain, snowfall (water content where applicable) sleet, graupel and hail. When the snow cumulates on the soil, also the snow depth has to be monitored. The ICOS Ecosystem Instruction documents are created and updated by the ICOS ETC on the basis of the respective official ICOS Ecosystem protocols. The intended use of these documents is to guide in an easy, direct, structured and harmonized way the station PI and staff through the application of the ICOS Ecosystem protocols. This document is structured in four different sections with the aim to facilitate the use and application: - Measurements: in this section the sensors, setup and methods to correctly collect the data and info are described. It includes sub-sections on sensors characteristics, practical indication for the setup/collection, info on the sampling design and guidelines for the installation/sampling also respect to other sensors/measurements - Maintenance: in this section all the maintenance and calibration guidelines are described, including the general timeline. - Submission: it is the section related to the data preparation and submission to the ETC. It includes the list of all the parameters, the correct formatting and the way to submit them to the database. It is linked to the BADM system needed to submit the metadata and not continuous measurements - Processing: this section is for internal use of the ETC and describes the processing applied to the single variable/info/sample submitted. It is important to remind that the exact application of the protocol at station level must be also discussed with the ETC in order to reach agreed solutions for specific cases. If a specific part is relevant only for a specific ecosystem or site Class this is also reported in the document.