Abstract: In a continuous effort to improve the environmental risk assessment of genetically modified crops, the European Food Safety Authority (EFSA) and the Netherlands Commission on Genetic Modification (COGEM) jointly organized an international workshop to review the latest scientific insights related to the assessment of potential adverse effects of Bt crops on non-target organisms (NTOs). The workshop was held on 29 and 30 November 2012 and was attended by parties from academia, national risk assessment bodies, industry, non-governmental organizations, the European Commission and EFSA. The workshop was divided into six sessions which respectively focused on the specificity of Bt proteins, species selection, the design of laboratory studies and field trials, and other challenging aspects related to NTO risk assessment. The closing session identified common views and remaining questions. Here, an overview of the main issues which were presented and discussed during the workshop is given.