Theme 1: Technical Aspects What are the current technical challenges to GHS implementation? differences in classification results using GHS criteria application of the ‘building block’ approach changing label and SDS formats lack of agreed international list of classified chemicals 2. What steps need to be taken by stakeholders (especially government and industry) to overcome these challenges in a coordinated way? 3. What further technical issues will be faced in the future and how should all stakeholders prepare to address them?