It is important for the success of any intervention to understand the existing system environment and user requirements. There has been limited study into the userrequirements of steel-fixers in the off-site fabrication of reinforced concrete and steel reinforcement. This work seeks to understand and specify the context in which steelfixers are working and identify the user-requirements. Steel-fixing video footage was analysed, enabling the production of targeted questions, which were then posed to industry experts at in-person site visits. The userrequirements are categorised into three groups: the users' safety & comfort, environmental, and task-specific requirements.