Background When providing activities to individuals with profound intellectual and multiple disabilities (PIMD), direct support persons (DSPs) often face questions that are, among other things, related to the alertness of the person with PIMD. While previous studies have revealed that stimulation might have a greater impact on levels of alertness than the internal conditions of the individual, they have also emphasized the importance of interaction in order to influence the level of alertness. Because the initiation of this interaction has been described as one of its core components, the present study has focused on the relationship between the stimuli presented, the initiation of the activity (by the person with PIMD or the DSP), and the level of alertness of the person with PIMD. Method Videotapes of the one‐to‐one interactions of 24 individuals with PIMD and their DSPs in multisensory environments have been scored using the Alertness Observation List. In a sequential analysis, the percentages of stimuli presented were related to the percentages of initiation. Furthermore, two other analyses focused on the relationship between the level of alertness and the preceding and subsequent percentages of initiation respectively. Results The results show that high percentages of the activities are initiated by the DSPs. In addition, activities that were initiated by the individual with PIMD were preceded and followed by higher percentages of alert behaviour than those initiated by the DSP. Outcomes differed for the different types of stimuli. Conclusions These results have striking implications for the lives of individuals with PIMD. It is quite possible that DSPs often act too quickly, whereas they would be better off waiting for a reaction on the part of their client. In general, DSPs need to find a balance between being passive themselves and promoting in the individual with PIMD a state of being as active and alert as possible.