The Assessment of Learning Powered mobility use (ALP) tool including the ALP instrument and facilitating strategies, was developed for Driving to Learn. This therapeutic intervention aims to provide children and adults who have profound cognitive disabilities with opportunities to learn tool use through powered mobility practise. To allow for longer intervention periods, a partnership was developed between professionals supervising Driving to Learn and persons accompanying children or adults to their practice sessions. Accompanying persons (relatives or assistants) gradually took on shared responsibility for applying the intervention and conducting assessments with the ALP-instrument. The aim of this study was to test the inter-rater reliability of the ALP-instrument version 2.0 as applied in this novel partnership in assessment and intervention. A psychometric analysis compared pair-wise assessments with the ALP-instrument version 2.0, made independently by professional supervisors and accompanying persons following each Driving to Learn session. Weighted kappa statistic was used to compare the matched pair ordinal data. Eight professional supervisors and 22 accompanying persons independently completed assessments with the ALP-instrument after 55 sessions with six children and five adults, who each participated in five Driving to Learn sessions. When the scores from the 55 pairs of assessments were compared, a weighted kappa value of 0.85 was obtained, indicating very good inter-rater reliability between the two rater groups. The resulting inter-rater reliability suggests that it is reliable to implement the ALP-instrument as part of partnership in intervention between supervisors and accompanying persons. Provision of longer periods of Driving to Learn is possible when those who accompany the child or adult are able to gradually assume responsibility for practice and assessment under the supervision of a professional. This partnership approach enables children and adults with multiple and complex disabilities to practise and learn in accordance with their conditions and needs. © 2020 Occupational Therapy Australia.