Bus controllers are an essential part of the London bus network. Although the bus driver is the individual directly in control of the vehicle, inputs from both the controller and driver influence operations. Currently, little research has focused on the dynamic between these parties, and how it works in the day-to-day operation of a bus. In the current study, data was collected across focus groups with controllers to understand the controller-driver relationship from the controller perspective. The objectives of the research were to: investigate interactions and working relationships between bus controllers and drivers in London and to explore the effect of controller/driver relationships on workload, stress and fatigue. It is clear that the working relationship between controllers and drivers is a challenging one, with both parties often misunderstanding the role of the other. This is made worse by the nature of communication via radio including poor quality audio leading to difficult interactions. All of the participating controllers expressed being overloaded with work, leading to feelings of stress and fatigue, with shift work and irregular hours being discussed as a cause of controller fatigue. Any steps taken to improve the difficult working relationship between drivers and controllers can be seen as beneficial because they could improve efficiency, worker wellbeing, and possibly safety.