Trade Statistics Branch of UN Statistics Division is responsible for the development and maintenance of the methodological guidelines on IMTS, including the Standard International Trade Classification (SITC) and related correspondence tables. As part of this work several surveys of national practices have been conducted.

Selected publications:

1. International Merchandise Trade Statistics: Concepts and Definitions, Revision 2 (1998)
2. International Merchandise Trade Statistics: Compiler's Manual (2004)
3. International Merchandise Trade Statistics: Supplement to the Compiler's Manual (2008)
4. International Merchandise Trade Statistics: Concepts and Definitions (IMTS 2010)
     (Available in Arabic, Chinese, English, French, Russian, and Spanish)
5. International Merchandise Trade Statistics: Compilers Manual, Revision 1 (IMTS 2010-CM)
     (Available in English, French, and Russian)
6. Statistical Territories of the World for Use in International Merchandise Trade Statistics (2005)

Complete list of IMTS related publications can be found at Trade Statistics Knowledgebase.

1. National Compilation and Reporting Practices in IMTS - Survey Results 2006 (and 1996)
2. National Practices in Compilation and Dissemination of External Trade Index Numbers: A Technical Report
3. Forthcoming 2017 Decennial Survey of National Compilation and Reporting Practices

1. Standard International Trade Classifications, Revision 4 (SITC, Rev. 4)
2. Harmonized Commodity Description and Coding Systems (HS) (WCO website)
3. Classification by Broad Economic Categories (BEC)
4. Complete HS and SITC conversion and correspondence tables along with detailed note on its conversion methodology
5. Additional Correspondence Tables (UNSD Classification website)