As part of the ‘EUP2P export control programme for arms-ATT’ (EUP2P-ATT), this workshop aimed to discuss the ratification status of the ATT in Cambodia and to assist the country in setting up a Draft Convention to tackle Arms Smuggling in the ASEAN region. The seminar examined the main legal obligations in the ATT – including the provisions on imports, transit and transshipment, brokering and diversion – and the arguments in favour of ratification, such as economic and security concerns. Cambodia’s Ministry of Interior presented its proposal for an ASEAN instrument to combat the trafficking of arms, a draft convention that was to be introduced at the ASEAN SOMTC Meeting in March 2016. The workshop also discussed how regional instruments can help to tackle the diversion of Small Arms and Light Weapons (SALW) and how they can best be aligned with the provisions of ATT. Examples of good practices from different EU member states were also presented and discussed.