The terms ‘single session therapy’ (SST) and ‘one‐at‐a‐time’ (OAAT) therapy are used to indicate a situation where the therapist and client set out with the expressed intention of helping the client in one session while acknowledging that additional sessions are available to the client. Both terms have their advantages and disadvantages and thus the author uses the blended term ‘single session one‐at‐a‐time’ (SST/OAAT) therapy to highlight the advantages of both. It is a core feature of SST/OAAT therapy that it is client‐centred especially where the session’s focus and goal are concerned. However, in an attempt to avoid SST/OAAT therapy being highjacked by therapists who operate from the ‘expert’ source of influence, the field has downplayed the contribution of the therapist’s expertise. In this paper, I make clear that the expertise of the therapist when allied to the expertise of the client can be a potent force for good in SST/OAAT therapy. My main task, however, is to outline my own approach to SST/OAAT therapy which is a blend of general principles that are likely to be held by the majority of SST/OAAT therapists and specific ideas that are derived from working with alliance theory, pluralism, and rational emotive behaviour therapy.