At the 12th meeting of the Conference of the Parties to the Convention on Biological Diversity, which took place in Pyeongchang, Republic of Korea, on 6-17 October 2014, one of the decisions made was to establish an Ad Hoc Technical Expert Group (AHTEG) on Synthetic Biology. A meeting of the AHTEG took place in Montreal, Canada on 21-25 September 2015. Substantive items on the meeting agenda included an operational definition of synthetic biology; the relationship between synthetic biology and biological diversity; and the similarities and differences between living modified organisms (as defined in the Cartagena Protocol) and organisms, components and products of synthetic biology techniques. Official and information documents prepared for the meeting, plus the meeting report, are available. See https://www.cbd.int/doc/?meeting=SYNBIOAHTEG-2015-01 or contact [email protected] for more information.