Ultimately risk and safety in transport operations is about people, organisations, and their interactions not only with technology and infrastructure, but also with each other. However, assessing how humans perform in safety critical situations poses considerable challenges. For example, how can we reliably measure such concepts as workload, fatigue and safety culture for operators such as pilots and bus drivers? And even if we could, what is an acceptable safe level of workload and fatigue for such operators? And what about the vulnerable users of transport systems, how best can help them navigate their daily challenges?