The ICES Working Group on Marine Shellfish Culture (WGMASC), chaired by Pauline Kamermans, held its tenth meeting in Sopot (Poland) on 20–23 March 2012. It was attended by 10 persons from 9 countries. The formal mandate and objectives of the meeting were to work on seven ToRs and to discuss two manuscripts based on finished ToRs. It was a joint meeting with WGEIM because of a request from SCICOM to discuss a plan for a new EG on Sustainable Aquaculture (ToR f). Subgroups were formed for ToR b (Site selection criteria in molluscan offshore aquaculture), ToR c (Aquaculture transfers between sites/countries - impact on wild stock and ToR d (Effects of climate change on shellfish aquaculture). ToR a (Identify emerging shellfish aquaculture issues and science advisory needs), ToR e (Develop a workplan for new Terms of Reference), ToR f (Collaborate with WGEIM to discuss how to revitalize the issue of sustainability in aquaculture) and ToR g (Collaboration with other EGs in relation to the ICES Science Plan) were addressed in a plenary sessions.