Soils contain globally about 1500 Pg carbon and so play an important role in the global carbon cycle. Soils can also act as carbon sinks contributing to remove CO2 from atmosphere. Thus also small changes in soil carbon stocks can have significant impact on climate change. Carboseq is a sub-project of the EJP project, involving 24 partner organizations from 23 European country. The main aim of the project to determine the theoretical sequestration potential of the European soils and to identify main carbon sequestration possibilities. These possibilities have to be feasible between the given socio-economic circumstances and must be based on technologies and practices that have been already proven. After harmonizing data from different partner countries the main objective of the project is to estimate organic carbon sequestration potential of the soils using two different approaches. The first approach is to estimate the increase in soil organic carbon stocks in cultivated agricultural areas and grasslands under eleven different agricultural management practices along the IPCC guidelines, taking into account socio-economic constraints and involving experts from partner countries. The second approach is to use the FAO global carbon sequestration map and the RothC model to estimate soil organic matter sequestration capacity at different time scales and under different future climate scenarios.