The behaviour of staff in a fire emergency can have a profound impact on the safety of occupants. This paper presents an analysis of staff behaviour in five unannounced evacuations of Marks and Spencer retail stores. The retail stores participating in the study comprised two three-storey city centre stores and one single storey out-of-town store in different locations in the United Kingdom. The evacuations were video taped using inhouse closed circuit television cameras (CCTV) orientated to cover pre-determined fields of view, and additional, portable cameras which were positioned and concealed when the stores were closed for business on the evenings before the evacuations. This paper presents an analysis of staff behaviour, and consequential impact on customers, as evidenced primarily from the video tapes and questionnaires administered to occupants as they evacuated the store. It was found that staff responses to the alarm, both in terms of time and nature of their responses, varied depending on the setting they were in and their associated responsibilities. Contrary to their training, they did not always respond immediately by evacuating customers but, in the majority of cases, first sought confirmation of the need to evacuate. They did, however, have a significant impact on customer response, not only in overcoming customers’ initial evacuation inertia but also in directing them towards suitable exits. This paper seeks to explain staff behaviour in the context of their training and discusses fire safety training in the context of management as an important consideration in performance based fire safety engineering design.