The International Data Assembly Centre compiles data received from national data offices and from core international GEOTRACES cruises. Global datasets are created for all key parameters, such as trace metals, e.g. iron (Fe), zinc (Zn), cadmium (Cd) and isotopic measurements e.g. nitrate (δ15NO3), carbon (δ13C), thorium (230Th), and made easily accessible to participating scientists and the larger science community. The policy for data release will be determined by the Scientific Steering Committee (SSC). The GEOTRACES International Data Assembly Centre (GDAC) works closely with the GEOTRACES steering committee and scientists to establish common metadata and format protocols. We are responsible for the quality control and secure archiving of the data that have been collected during international core GEOTRACES cruises. Data will be submitted to national archive facilities; our aim is to integrate core GEOTRACES data into a global data set.