Following on from FAL Bulletin No. 372 concerning the new regulation on sulphur emissions from maritime transport, the aim of this document is to present the methodology for calculating CO2 emissions generated by maritime transport in international trade. This methodology was used to obtain a preliminary estimate of emissions from a representative sample of exports from Latin America and the Caribbean. The sample was obtained from export tonnages from eight countries in 2017, and represents nearly 70% of total regional exports.