8.1. Introduction. The present chapter describes data processing and database management at customs and at the statistical agency responsible for the overall compilation of international merchandise trade statistics (the responsible agency). It describes the characteristics and functions of these systems, giving the Automated System for Customs Data (ASYCUDA), Eurotrace and national systems as examples. Further, it describes the data fields necessary for statistical purposes and how to obtain these data from the customs records. This chapter logically follows chapter VII which discusses the integration of data from different sources, and precedes chapter IX, which discusses quality assurance, measurement and reporting.