This document describes how to organize, set up, and collect the measurements of soil-meteorological variables at ICOS ecosystem stations. These variables are soil temperature, volumetric soil water content, and soil heat flux density. Measurements of water table depth, another soil-meteorological variable, are explained in a separate Instructions document. 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. - 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 site level must be also discussed with 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.