The Barcelona Expert Center (BEC), created in 2007, is a European Space Agency (ESA) Expert Support Laboratory to SMOS missions at Levels 1 and 2. Since its beginning, BEC has provided support not only in calibration and validation activities, but also in the design and development of higher level products (Levels 3 and 4). Since 2013, BEC is the Spanish center in charge of the production of SMOS products, both on land and on ocean, and with the goal to expand its activities to other variables and missions (see http://bec.icm.csic.es/). The great advantage of BEC, as it integrates all the processing chain from level 1 to level 4, is that BEC products benefit of critical improvements in the processing at any level.