This document describes how to collect and prepare soil samples to monitor the soil organic Carbon and Nitrogen Stocks (CNS) within the target area of an EC flux tower. The stocks are calculated for the first meter (0 to 100 cm). The CNS will be determined from simultaneous measurements of soil organic carbon and nitrogen contents and bulk density. Whereas the C and N contents of soil samples are determined by the ETC central laboratory, the soil density must be measured by the station team. This document is structured in different sections with the aim to facilitate the use and application: - Objectives and Definitions - Overview of the soil sampling activities - Soil sampling: description of the methods available to collect samples according to soil characteristics (soil texture, structure, stoniness, root content) - Sample processing: description of available methods for soil preparation (drying and sieving), measurement of physical parameters (water content and stoniness), compositing and reduction to constitute the laboratory and archive soil samples - Calculation and data submission: description of the sample identification and shipping to the soil analysis laboratory and soil archive facility, 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 non-continuous measurements. - Maintenance of tools It is important to remind that the exact application of the protocol at station 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 station Class this is also reported in the document.