Rapport is widely considered to be an essential component in the development of an effective therapeutic relationship between health-service professionals and their clients. Studies have shown that a positive rapport is associated with reduced rates of challenging behaviour among clients with developmental disabilities. However, to-date, there is limited research exploring whether therapeutic rapport affects client skill acquisition. Therefore, the current study aimed to systematically train four behavioural therapists in presession pairing techniques and evaluated the impact on life skill acquisition rates among a group of eight children with autism, using a multiple baseline across participants design. Improvement rate difference (IRD) was calculated for each participant and omnibus IRDs showed a modest impact of presession pairing on skill acquisition. Considering that systematic prompting and task analysis procedures were used across all phases of this study, these results are discussed in the context of highlighting the importance of upskilling, already skilled therapists, in rapport building techniques, to maximise client gains.