This study aims to systematically map and assess performance requirements for collision avoidance manoeuvring for two cases. A case where the navigator performs collision avoidance, and a case where collision avoidance is performed by collision avoidance system where the navigator acts as its supervisor. An appraisal of collision avoidance manoeuvring was performed based on three data sources: the collision avoidance regulations, a ferry operator’s procedures, and interviews with navigators including in situ observations. A framework was established in which the gathered data was structured and analysed using a cognitive task analysis approach. Based on the results, performance requirements and information needs were established. Further work will focus on detailing the navigator’s information needs and the corresponding system’s transparency requirements to support effective human performance.