Task shifting has enabled South Africa (SA) to rapidly expand its HIV treatment programme. This has been achieved by training and mentoring primary-care nurses in nurse initiation and management of antiretroviral therapy (NIMART). Five years into its clinical mentoring programme, the Foundation for Professional Development conducted an evaluation that identified improved knowledge, attitudes and confidence perceived by nurses who received NIMART mentoring. Low completion rates for the Department of Health (DoH) NIMART training process were identified and therefore targeted mentoring was introduced; this increased the percentage of primary nurses eligible for DoH certificates of clinical competence in NIMART from 12%, adding a further 30%. There remain a large number of primary nurses who require mentoring in order to complete the NIMART process. For those who have completed the process, there remains a need for ongoing mentoring as SA's HIV programme evolves, complex cases emerge and primary care undergoes change.